bpo-34041: Allow creating deterministic functions in Connection.create_function() (GH-8086)

1 files changed, 9 insertions, 2 deletions

diff --git a/Doc/library/sqlite3.rst b/Doc/library/sqlite3.rst
index efc74a6..d30e4d4 100644
--- a/Doc/library/sqlite3.rst
+++ b/Doc/library/sqlite3.rst
@@ -337,17 +337,24 @@ Connection Objects
       :meth:`~Cursor.executescript` method with the given *sql_script*, and
       returns the cursor.
 
-   .. method:: create_function(name, num_params, func)
+   .. method:: create_function(name, num_params, func, *, deterministic=False)
 
       Creates a user-defined function that you can later use from within SQL
       statements under the function name *name*. *num_params* is the number of
       parameters the function accepts (if *num_params* is -1, the function may
       take any number of arguments), and *func* is a Python callable that is
-      called as the SQL function.
+      called as the SQL function. If *deterministic* is true, the created function
+      is marked as `deterministic <https://sqlite.org/deterministic.html>`_, which
+      allows SQLite to perform additional optimizations. This flag is supported by
+      SQLite 3.8.3 or higher, ``sqlite3.NotSupportedError`` will be raised if used
+      with older versions.
 
       The function can return any of the types supported by SQLite: bytes, str, int,
       float and ``None``.
 
+      .. versionchanged:: 3.8
+         The *deterministic* parameter was added.
+
       Example:
 
       .. literalinclude:: ../includes/sqlite3/md5func.py