:released: January 21, 2026

.. change::

:tags: bug, sqlite

:tickets: 13039

Fixed issue in the aiosqlite driver where SQLAlchemy's setting of

aiosqlite's worker thread to "daemon" stopped working because the aiosqlite

architecture moved the location of the worker thread in version 0.22.0.

This "daemon" flag is necessary so that a program is able to exit if the

SQLite connection itself was not explicitly closed, which is particularly

likely with SQLAlchemy as it maintains SQLite connections in a connection

pool. While it's perfectly fine to call :meth:`.AsyncEngine.dispose`

before program exit, this is not historically or technically necessary for

any driver of any known backend, since a primary feature of relational

databases is durability. The change also implements support for

"terminate" with aiosqlite when using version version 0.22.1 or greater,

which implements a sync ``.stop()`` method.

.. change::

:tags: usecase, mssql

:tickets: 13045

Added support for the ``IF EXISTS`` clause when dropping indexes on SQL

Server 2016 (13.x) and later versions. The :paramref:`.DropIndex.if_exists`

parameter is now honored by the SQL Server dialect, allowing conditional

index drops that will not raise an error if the index does not exist.

Pull request courtesy Edgar Ramírez Mondragón.

.. change::

:tags: bug, postgresql

:tickets: 13059

Fixed issue where PostgreSQL JSONB operators

:meth:`_postgresql.JSONB.Comparator.path_match` and

:meth:`_postgresql.JSONB.Comparator.path_exists` were applying incorrect

``VARCHAR`` casts to the right-hand side operand when used with newer

PostgreSQL drivers such as psycopg. The operators now indicate the

right-hand type as ``JSONPATH``, which currently results in no casting

taking place, but is also compatible with explicit casts if the

implementation were require it at a later point.

.. change::

:tags: bug, postgresql

:tickets: 13067

Fixed regression in PostgreSQL dialect where JSONB subscription syntax

would generate incorrect SQL for :func:`.cast` expressions returning JSONB,

causing syntax errors. The dialect now properly wraps cast expressions in

parentheses when using the ``[]`` subscription syntax, generating

``(CAST(...))[index]`` instead of ``CAST(...)[index]`` to comply with

PostgreSQL syntax requirements. This extends the fix from :ticket:`12778`

which addressed the same issue for function calls.

.. change::

:tags: bug, mariadb

:tickets: 13070

Fixed the SQL compilation for the mariadb sequence "NOCYCLE" keyword that

is to be emitted when the :paramref:`.Sequence.cycle` parameter is set to

False on a :class:`.Sequence`. Pull request courtesy Diego Dupin.

.. change::

:tags: bug, typing

:tickets: 13075

Fixed typing issues where ORM mapped classes and aliased entities could not

be used as keys in result row mappings or as join targets in select

statements. Patterns such as ``row._mapping[User]``,

``row._mapping[aliased(User)]``, ``row._mapping[with_polymorphic(...)]``

(rejected by both mypy and Pylance), and ``.join(aliased(User))``

(rejected by Pylance) are documented and fully supported at runtime but

were previously rejected by type checkers. The type definitions for

:class:`._KeyType` and :class:`._FromClauseArgument` have been updated to

accept these ORM entity types.

.. change::

:tags: bug, postgresql

Improved the foreign key reflection regular expression pattern used by the

PostgreSQL dialect to be more permissive in matching identifier characters,

allowing it to correctly handle unicode characters in table and column

names. This change improves compatibility with PostgreSQL variants such as

CockroachDB that may use different quoting patterns in combination with

unicode characters in their identifiers. Pull request courtesy Gord

Thompson.