2.0.50

Released: May 24, 2026

orm

• [orm] [bug] Fixed issue where using _orm.joinedload() with PropComparator.of_type() targeting a joined-table subclass combined with PropComparator.and_() referencing a column on that subclass would generate invalid SQL, where the subclass column was not adapted to the subquery alias. Pull request courtesy Joaquin Hui Gomez.

  References: #13203

• [orm] [bug] Fixed issue where the presence of a SessionEvents.do_orm_execute() event hook would cause internal execution options such as yield_per and loader-specific state from the first orm_pre_session_exec pass to leak into the second pass, leading to errors when using relationship loaders such as selectinload() and immediateload(). The execution options passed to the second compilation pass are now based on the original options plus only the explicit updates made via ORMExecuteState.update_execution_options() within the event hook.

  References: #13301

• [orm] [bug] Fixed issue where using _orm.with_polymorphic() on a leaf class (a subclass with no further descendants) or a non-inherited class would fail with an AttributeError when used in an ORM statement, due to _orm.configure_mappers() not being triggered implicitly. The fix ensures that AliasedInsp participates in the _post_inspect hook, triggering mapper configuration during ORM statement compilation.

  References: #13319

sql

• [sql] [bug] Fixed issue where floor division (//) between a Float or Numeric numerator and an Integer denominator would omit the FLOOR() SQL wrapper on dialects where Dialect.div_is_floordiv is True (the default, including PostgreSQL and SQLite). FLOOR() is now applied if either the denominator or the numerator is a non-integer, so that expressions such as float_col // int_col render as FLOOR(float_col / int_col) instead of the incorrect float_col / int_col. Pull request courtesy r266-tech.

  References: #10528

postgresql

• [postgresql] [bug] Improve handling of two phase transaction identifiers for PostgreSQL when the identifier is provided by the user. As part of this change the psycopg dialect was updated to use the DBAPI two phase transaction API instead of executing the SQL directly.

  References: #13229

• [postgresql] [bug] Fixed issue where the asyncpg driver could throw an insufficiently-handled exception InternalClientError under some circumstances, leading to connections not being properly marked as invalidated.

  References: #13241

• [postgresql] [bug] Fixed issue where the ExcludeConstraint construct did not correctly forward the ExcludeConstraint.info parameter to the superclass, causing user-defined metadata to be lost. Pull request courtesy Wiktor Byrka.

  References: #13317

mysql

• [mysql] [bug] [reflection] Narrowed the scope of the internal workaround for MySQL bugs #88718 and #96365 so that it is only applied where needed: MySQL 8.0.1 through 8.0.13 (where bug 88718 is present), and on systems with lower_case_table_names=2 (where bug 96365 applies, typically macOS). Previously the workaround was applied unconditionally for all MySQL 8.0+ versions, which caused a KeyError during foreign key reflection when the database user lacked SELECT privileges on referred tables.

  References: #13243

• [mysql] [bug] Fixed issue in aiomysql and asyncmy dialects that appears as of using pymysql 1.2.0; the dialects were not properly taking into account logic that detects the argument signature of pymysql's ping() method which was added as part of #10492.

  References: #13306

sqlite

• [sqlite] [bug] Escape key and pragma values when utilizing the pysqlcipher dialect.

  References: #13230