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author | axis <qt-info@nokia.com> | 2009-04-24 11:34:15 (GMT) |
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committer | axis <qt-info@nokia.com> | 2009-04-24 11:34:15 (GMT) |
commit | 8f427b2b914d5b575a4a7c0ed65d2fb8f45acc76 (patch) | |
tree | a17e1a767a89542ab59907462206d7dcf2e504b2 /doc/src/snippets/code/src_sql_kernel_qsqldatabase.cpp | |
download | Qt-8f427b2b914d5b575a4a7c0ed65d2fb8f45acc76.zip Qt-8f427b2b914d5b575a4a7c0ed65d2fb8f45acc76.tar.gz Qt-8f427b2b914d5b575a4a7c0ed65d2fb8f45acc76.tar.bz2 |
Long live Qt for S60!
Diffstat (limited to 'doc/src/snippets/code/src_sql_kernel_qsqldatabase.cpp')
-rw-r--r-- | doc/src/snippets/code/src_sql_kernel_qsqldatabase.cpp | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/doc/src/snippets/code/src_sql_kernel_qsqldatabase.cpp b/doc/src/snippets/code/src_sql_kernel_qsqldatabase.cpp new file mode 100644 index 0000000..8194611 --- /dev/null +++ b/doc/src/snippets/code/src_sql_kernel_qsqldatabase.cpp @@ -0,0 +1,95 @@ +//! [0] +// WRONG +QSqlDatabase db = QSqlDatabase::database("sales"); +QSqlQuery query("SELECT NAME, DOB FROM EMPLOYEES", db); +QSqlDatabase::removeDatabase("sales"); // will output a warning + +// "db" is now a dangling invalid database connection, +// "query" contains an invalid result set +//! [0] + + +//! [1] +{ + QSqlDatabase db = QSqlDatabase::database("sales"); + QSqlQuery query("SELECT NAME, DOB FROM EMPLOYEES", db); +} +// Both "db" and "query" are destroyed because they are out of scope +QSqlDatabase::removeDatabase("sales"); // correct +//! [1] + + +//! [2] +QSqlDatabase::registerSqlDriver("MYDRIVER", + new QSqlDriverCreator<MyDatabaseDriver>); +QSqlDatabase db = QSqlDatabase::addDatabase("MYDRIVER"); +//! [2] + + +//! [3] +... +db = QSqlDatabase::addDatabase("QODBC"); +db.setDatabaseName("DRIVER={Microsoft Access Driver (*.mdb)};FIL={MS Access};DBQ=myaccessfile.mdb"); +if (db.open()) { + // success! +} +... +//! [3] + + +//! [4] +... +// MySQL connection +db.setConnectOptions("CLIENT_SSL=1;CLIENT_IGNORE_SPACE=1"); // use an SSL connection to the server +if (!db.open()) { + db.setConnectOptions(); // clears the connect option string + ... +} +... +// PostgreSQL connection +db.setConnectOptions("requiressl=1"); // enable PostgreSQL SSL connections +if (!db.open()) { + db.setConnectOptions(); // clear options + ... +} +... +// ODBC connection +db.setConnectOptions("SQL_ATTR_ACCESS_MODE=SQL_MODE_READ_ONLY;SQL_ATTR_TRACE=SQL_OPT_TRACE_ON"); // set ODBC options +if (!db.open()) { + db.setConnectOptions(); // don't try to set this option + ... +} +//! [4] + + +//! [5] +#include "qtdir/src/sql/drivers/psql/qsql_psql.cpp" +//! [5] + + +//! [6] +PGconn *con = PQconnectdb("host=server user=bart password=simpson dbname=springfield"); +QPSQLDriver *drv = new QPSQLDriver(con); +QSqlDatabase db = QSqlDatabase::addDatabase(drv); // becomes the new default connection +QSqlQuery query; +query.exec("SELECT NAME, ID FROM STAFF"); +... +//! [6] + + +//! [7] +unix:LIBS += -lpq +win32:LIBS += libpqdll.lib +//! [7] + + +//! [8] +QSqlDatabase db; +qDebug() << db.isValid(); // Returns false + +db = QSqlDatabase::database("sales"); +qDebug() << db.isValid(); // Returns true if "sales" connection exists + +QSqlDatabase::removeDatabase("sales"); +qDebug() << db.isValid(); // Returns false +//! [8] |