.. changelog::
:version: 2.0.52
- :include_notes_from: unreleased_20
+ :released: August 11, 2026
+
+ .. change::
+ :tags: bug, postgresql, reflection
+ :tickets: 13157
+
+ Fixed reflection of PostgreSQL CHECK constraints where an expression made
+ up of multiple parenthesized sub-expressions, such as ``(x IS NULL OR y IS
+ NULL) AND (x IS NULL OR y IS NULL)``, would have its leading and trailing
+ parentheses incorrectly stripped, producing an unbalanced and
+ syntactically invalid reflected expression. Pull request courtesy
+ Shaurya Singh.
+
+ .. change::
+ :tags: bug, mssql
+ :tickets: 13380
+
+ Tightened the construction of the ODBC connection string in the pyodbc
+ connector (as well as the mssql-python connector in 2.1) so that the
+ driver name, the names of pass-through connection parameters, and values
+ containing ``}`` are brace-quoted. Previously a ``}`` in the driver name
+ or in a pass-through value, or a ``;`` in the name of a pass-through
+ parameter, could close the surrounding token early and allow the
+ remainder of the string to be interpreted as additional connection
+ attributes. Pull request courtesy dxbjavid.
+
+ .. change::
+ :tags: bug, orm declarative
+ :tickets: 13386
+
+ Fixed issue where using :pep:`593` ``Annotated`` wrapping a :pep:`695`
+ ``type`` alias, such as ``Annotated[SomeTypeAlias, mapped_column()]``,
+ would crash with ``AttributeError: __value__``. The internal
+ ``is_pep695()`` check incorrectly identified the ``Annotated`` type as a
+ PEP 695 type alias due to a quirk in ``Annotated.__origin__`` returning
+ the first type argument rather than ``Annotated`` itself.
+
+ .. change::
+ :tags: bug, tests
+ :tickets: 13392
+
+ Fixed class-scoped pytest fixtures that were defined as instance methods
+ using ``self``, which is deprecated as of pytest 9.1 and will be removed in
+ pytest 10. Fixtures are now decorated with a compatibility ``@classmethod``
+ decorator and use ``cls`` as the first parameter.
+
+ .. change::
+ :tags: bug, sql
+ :tickets: 13396
+
+ Fixed issue where :meth:`_sql.Select.get_final_froms` would emit a
+ deprecation warning when the statement made use of the PostgreSQL-specific
+ expression argument to :meth:`_sql.Select.distinct`; the same spurious
+ warning would be emitted when stringifying such a statement without
+ explicitly using a PostgreSQL dialect. The fix ensures that this 1.4-era
+ warning is suppressed under both 2.0 and 2.1.
+
+ Note that under SQLAlchemy 2.1, passing an expression to
+ :meth:`_sql.Select.distinct` is deprecated overall, and is replaced by a
+ new PostgreSQL-specific construct (see :ticket:`12342`).
+
+ .. change::
+ :tags: bug, sqlite
+ :tickets: 13419
+
+ Reworked the regular expression that detects inline ``UNIQUE`` column
+ constraints during SQLite ``CREATE TABLE`` reflection so that the
+ whitespace separating a column's type from a following clause is matched
+ unambiguously. The previous pattern had three overlapping quantifiers
+ that could each consume a space character, so a column definition
+ carrying a long run of whitespace in the stored schema made
+ :meth:`_reflection.Inspector.get_unique_constraints` spend cubic time
+ backtracking before returning. Fix courtesy of Javid Khan.
+
+ .. change::
+ :tags: bug, sql
+ :tickets: 13424
+
+ Fixed an issue in :class:`.Numeric` where the
+ :paramref:`.Numeric.decimal_return_scale` parameter was ignored when the
+ DBAPI does not support native decimal objects (i.e.
+ ``dialect.supports_native_decimal`` is ``False``). In this path the result
+ processor was computing the conversion scale from
+ :paramref:`.Numeric.scale` directly, bypassing
+ :paramref:`.Numeric.decimal_return_scale` entirely. The behavior now
+ matches :class:`.Float`, which already used the correct
+ ``_effective_decimal_return_scale`` property. Pull request courtesy Kadir
+ Can Ozden.
+
+ .. change::
+ :tags: bug, postgresql
+ :tickets: 13429
+
+ Fixed bug in the PostgreSQL dialect where a single quote in a sequence,
+ table, or schema name, such as one supplied via a ``schema_translate_map``
+ or an explicit :class:`.Sequence`, could result in a malformed
+ ``nextval()`` statement. The quote is now properly escaped. Pull request
+ courtesy dxbjavid.
+
+ .. change::
+ :tags: bug, orm
+ :tickets: 13439
+
+ 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.
+
+ .. change::
+ :tags: bug, sql
+ :tickets: 13448
+
+ Added auditing to the test suite which exercises the literal execute
+ processors across all datatypes and dialects to ensure that string input is
+ either appropriately rejected or correctly escaped. Literal execute
+ processors are invoked when the :paramref:`.bindparam.literal_execute`
+ parameter is used with an explicit :func:`.bindparam` object, which
+ overrides DBAPI-native bind handling to render the value inline with the
+ statement instead. Datatypes that were updated include the originally
+ reported SQL Server ``Uuid`` / ``UNIQUEIDENTIFIER`` rendering which now
+ escapes properly, the :class:`.JSONPATH` type that's currently
+ PostgreSQL-only, and a full family of numeric types stemming from the
+ :class:`_types.Float` and :class:`_types.Numeric` bases which now coerce
+ the value to a number, rejecting non-numeric input. Thanks to Javid Khan
+ for helping to identify the issue.
+
+ .. change::
+ :tags: bug, platform
+ :tickets: 13477
+
+ Python 3.15 support has been added and tested, including minimal changes
+ for full compatibility.
+
+ .. change::
+ :tags: bug, schema
+ :tickets: 13481
+
+ Fixed an issue where :meth:`_schema.Table.to_metadata` reused column
+ default and on-update objects, causing the defaults on the original
+ columns to refer to the copied columns. Default generators, including
+ sequences, and server-side defaults are now copied and remain associated
+ with their respective columns and metadata collections. Applications that
+ inspected these objects will now see distinct defaults on the copied table
+ instead of the objects owned by the original table. Pull request courtesy
+ Goutam Adwant.
+
+ .. change::
+ :tags: bug, orm
+ :tickets: 13485
+
+ Fixed bug where a failed :meth:`_orm.Session.bulk_insert_mappings`,
+ :meth:`_orm.Session.bulk_update_mappings` or
+ :meth:`_orm.Session.bulk_save_objects` call could leave the
+ :class:`_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 :meth:`_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
+ :meth:`_orm.Session.rollback` nor :meth:`_orm.Session.close` would clear
+ it, and every subsequent flush would raise ``InvalidRequestError: Session
+ is already flushing``. Pull request courtesy Hamody We.
+
+ .. change::
+ :tags: bug, orm
+ :tickets: 13493
+
+ Fixed issue where unpickling an ORM object that were loaded using loader
+ options making use of wildcard tokens, such as :func:`_orm.load_only` or
+ :func:`_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.
+
+ .. change::
+ :tags: bug, orm
+ :tickets: 13493
+
+ Fixed issue where a string ending in ``"*"`` passed to a
+ :class:`_orm.Load` strategy method, such as
+ ``Load(A).joinedload("bs.*")``, would bypass the check which rejects
+ string attribute names in loader options, silently producing a loader
+ path that matched nothing. Such a string now raises
+ :class:`.ArgumentError` with the same message given for any other
+ string attribute name. The bare wildcard ``"*"``, as in
+ ``Load(A).lazyload("*")``, continues to be accepted.
+
+ .. change::
+ :tags: bug, orm
+ :tickets: 6274
+
+ Calling :func:`_orm.aliased` against a :func:`_sql.select` or
+ :func:`_sql.union` / :class:`_sql.CompoundSelect` construct, which
+ previously failed with an obscure ``AttributeError`` regarding a missing
+ ``.mapper`` attribute, now raises when using SQLAlchemy 2.1, and emits a
+ deprecation warning under SQLAlchemy 2.0 as it coerces the construct into a
+ subquery instead. This matches the behavior of other similar implicit
+ SELECT-to-FROM coercions. Pull request courtesy Rens Groothuijsen.
.. changelog::
:version: 2.0.51
projects / thirdparty / sqlalchemy / sqlalchemy.git / commitdiff
