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authorMike Bayer <mike_mp@zzzcomputing.com>2023-04-05 19:27:10 -0400
committerMike Bayer <mike_mp@zzzcomputing.com>2023-04-05 19:27:10 -0400
commit582e4184ad2af8300fcf7742afb12db09c0a03c8 (patch)
tree9d450f5367dc91da03f26f8c02bbfb39b6522a18 /doc
parent7fb7365622ee751b264bbbd4e7394ef8e81d45c5 (diff)
downloadsqlalchemy-582e4184ad2af8300fcf7742afb12db09c0a03c8.tar.gz
revise changelog for #9586
this would be misleading due to #9603 disabling insertmanyvalues across the board. Change-Id: I0e746e13f8ad054207790644cb43eba101dde30c
Diffstat (limited to 'doc')
-rw-r--r--doc/build/changelog/unreleased_20/9586.rst17
1 files changed, 8 insertions, 9 deletions
diff --git a/doc/build/changelog/unreleased_20/9586.rst b/doc/build/changelog/unreleased_20/9586.rst
index d8abe1a5f..4dce60d63 100644
--- a/doc/build/changelog/unreleased_20/9586.rst
+++ b/doc/build/changelog/unreleased_20/9586.rst
@@ -6,16 +6,15 @@
pyodbc when ``fast_executemany`` is set to ``True`` by using
``fast_executemany`` / ``cursor.executemany()`` for bulk INSERT that does
not include RETURNING, restoring the same behavior as was used in
- SQLAlchemy 1.4 when this parameter is set. For INSERT statements that use
- RETURNING, the "insertmanyvalues" strategy continues to be used as it is
- the only current strategy that supports RETURNING with bulk INSERT.
-
- Previously, SQLAlchemy 2.0 would use "insertmanyvalues" for all INSERT
- statements when ``use_insertmanyvalues`` was left at its default of
- ``False``, ignoring if ``fast_executemany`` was set.
+ SQLAlchemy 1.4 when this parameter is set.
New performance details from end users have shown that ``fast_executemany``
is still much faster for very large datasets as it uses ODBC commands that
can receive all rows in a single round trip, allowing for much larger
- datasizes than the batches that can be sent by the current
- "insertmanyvalues" strategy.
+ datasizes than the batches that can be sent by "insertmanyvalues"
+ as was implemented for SQL Server.
+
+ While this change was made such that "insertmanyvalues" continued to be
+ used for INSERT that includes RETURNING, as well as if ``fast_executemany``
+ were not set, due to :ticket:`9603`, the "insertmanyvalues" strategy has
+ been disabled for SQL Server across the board in any case.