2.0.40

Released: March 27, 2025

orm

• [orm] [bug] Fixed regression which occurred as of 2.0.37 where the checked ArgumentError that's raised when an inappropriate type or object is used inside of a Mapped annotation would raise TypeError with "boolean value of this clause is not defined" if the object resolved into a SQL expression in a boolean context, for programs where future annotations mode was not enabled. This case is now handled explicitly and a new error message has also been tailored for this case. In addition, as there are at least half a dozen distinct error scenarios for intepretation of the Mapped construct, these scenarios have all been unified under a new subclass of ArgumentError called MappedAnnotationError, to provide some continuity between these different scenarios, even though specific messaging remains distinct.

  References: #12329

• [orm] [bug] Fixed regression in ORM Annotated Declarative class interpretation caused by typing_extension==4.13.0 that introduced a different implementation for TypeAliasType while SQLAlchemy assumed that it would be equivalent to the typing version, leading to pep-695 type annotations not resolving to SQL types as expected.

  References: #12473

sql

• [sql] [usecase] Implemented support for the GROUPS frame specification in window functions by adding _sql.over.groups option to _sql.over() and FunctionElement.over(). Pull request courtesy Kaan Dikmen.

  References: #12450

• [sql] [bug] Fixed issue in CTE constructs involving multiple DDL _sql.Insert statements with multiple VALUES parameter sets where the bound parameter names generated for these parameter sets would conflict, generating a compile time error.

  References: #12363

• [sql] [bug] Fixed regression caused by #7471 leading to a SQL compilation issue where name disambiguation for two same-named FROM clauses with table aliasing in use at the same time would produce invalid SQL in the FROM clause with two "AS" clauses for the aliased table, due to double aliasing.

  References: #12451

asyncio

• [asyncio] [bug] Fixed issue where AsyncSession.get_transaction() and AsyncSession.get_nested_transaction() would fail with NotImplementedError if the "proxy transaction" used by AsyncSession were garbage collected and needed regeneration.

  References: #12471

postgresql

• [postgresql] [usecase] Added support for specifying a list of columns for SET NULL and SET DEFAULT actions of ON DELETE clause of foreign key definition on PostgreSQL. Pull request courtesy Denis Laxalde.

  References: #11595

• [postgresql] [usecase] When building a PostgreSQL ARRAY literal using _postgresql.array with an empty clauses argument, the _postgresql.array.type_ parameter is now significant in that it will be used to render the resulting ARRAY[] SQL expression with a cast, such as ARRAY[]::INTEGER. Pull request courtesy Denis Laxalde.

  References: #12432

mysql

• [mysql] [bug] Support has been re-added for the MySQL-Connector/Python DBAPI using the mysql+mysqlconnector:// URL scheme. The DBAPI now works against modern MySQL versions as well as MariaDB versions (in the latter case it's required to pass charset/collation explicitly). Note however that server side cursor support is disabled due to unresolved issues with this driver.

  References: #12332

• [mysql] [bug] Fixed issue in MySQL server default reflection where a default that has spaces would not be correctly reflected. Additionally, expanded the rules for when to apply parenthesis to a server default in DDL to suit the general case of a default string that contains non-word characters such as spaces or operators and is not a string literal.

  References: #12425

sqlite

• [sqlite] [bug] Expanded the rules for when to apply parenthesis to a server default in DDL to suit the general case of a default string that contains non-word characters such as spaces or operators and is not a string literal.

  References: #12425