diff options
Diffstat (limited to 'lib/sqlalchemy/dialects/mssql/pyodbc.py')
| -rw-r--r-- | lib/sqlalchemy/dialects/mssql/pyodbc.py | 19 |
1 files changed, 6 insertions, 13 deletions
diff --git a/lib/sqlalchemy/dialects/mssql/pyodbc.py b/lib/sqlalchemy/dialects/mssql/pyodbc.py index 08c6bc48f..6af527e73 100644 --- a/lib/sqlalchemy/dialects/mssql/pyodbc.py +++ b/lib/sqlalchemy/dialects/mssql/pyodbc.py @@ -290,19 +290,6 @@ Pyodbc have been resolved as of SQLAlchemy 2.0.5. See the notes at Fast Executemany Mode --------------------- - .. note:: SQLAlchemy 2.0 introduced the :ref:`engine_insertmanyvalues` - feature for SQL Server, which is used by default to optimize many-row - INSERT statements; however as of SQLAlchemy 2.0.9 this feature had - to be turned off for SQL Server as the database does not support - deterministic RETURNING of INSERT rows for a multi-row INSERT statement. - -.. versionchanged:: 2.0.9 - ``fast_executemany`` executions will be used - for INSERT statements that don't include RETURNING, when - ``fast_executemany`` is set. Previously, ``use_insertmanyvalues`` would - cause ``fast_executemany`` to not be used in most cases. - - ``use_insertmanyvalues`` is disabled for SQL Server overall as of 2.0.9. - The PyODBC driver includes support for a "fast executemany" mode of execution which greatly reduces round trips for a DBAPI ``executemany()`` call when using Microsoft ODBC drivers, for **limited size batches that fit in memory**. The @@ -316,6 +303,12 @@ Server dialect supports this parameter by passing the "mssql+pyodbc://scott:tiger@mssql2017:1433/test?driver=ODBC+Driver+17+for+SQL+Server", fast_executemany=True) +.. versionchanged:: 2.0.9 - the ``fast_executemany`` parameter now has its + intended effect of this PyODBC feature taking effect for all INSERT + statements that are executed with multiple parameter sets, which don't + include RETURNING. Previously, SQLAlchemy 2.0's :term:`insertmanyvalues` + feature would cause ``fast_executemany`` to not be used in most cases + even if specified. .. versionadded:: 1.3 |