Sourced from sqlalchemy's releases.

2.0.52

Released: August 11, 2026

platform

• [platform] [bug] Python 3.15 support has been added and tested, including minimal changes for full compatibility.

  References: #13477

orm

• [orm] [bug] Fixed a result-column misalignment bug in ORM-enabled UPDATE statements where synchronize_session="fetch" is in use, either explicitly or because the statement uses constructs such as CTEs that implicitly select for it. Columns in rows returned by .returning() could be returned under incorrect keys (e.g. row[SomeClass.a] returning the value of a different column), a problem most likely to manifest under concurrent workloads. ORM DELETE statements were not affected.

  References: #13439

• [orm] [bug] Fixed bug where a failed _orm.Session.bulk_insert_mappings(), _orm.Session.bulk_update_mappings() or _orm.Session.bulk_save_objects() call could leave the _orm.Session permanently in a "flushing" state, such as when the transaction could not be begun because a previous flush had left it needing a rollback. Unlike _orm.Session.flush(), the bulk methods set the internal flushing flag and began the transaction outside of the try/finally block that resets it, so that neither _orm.Session.rollback() nor _orm.Session.close() would clear it, and every subsequent flush would raise InvalidRequestError: Session is already flushing. Pull request courtesy Hamody We.

  References: #13485

• [orm] [bug] Fixed issue where unpickling an ORM object that were loaded using loader options making use of wildcard tokens, such as _orm.load_only() or _orm.raiseload() with "*", would fail with KeyError or IndexError if the process doing the unpickling had not yet constructed a loader path making use of that same token. This would typically be observed when the object were unpickled in a separate process, such as with the spawn or forkserver multiprocessing start methods, the latter of which became the default on POSIX platforms as of Python 3.14. The internal collection of these tokens is now established up front, so that it is identical in every process.

... (truncated)

• See full diff in compare view