2.0.35

Released: September 16, 2024

orm

• [orm] [bug] [typing] Fixed issue where it was not possible to use typing.Literal with
  Mapped[] on Python 3.8 and 3.9. Pull request courtesy Frazer McLean.

  References: #11820

• [orm] [bug] Fixed issue in ORM evaluator where two datatypes being evaluated with the
  SQL concatenator operator would not be checked for
  UnevaluatableError based on their datatype; this missed the case
  of _postgresql.JSONB values being used in a concatenate operation
  which is supported by PostgreSQL as well as how SQLAlchemy renders the SQL
  for this operation, but does not work at the Python level. By implementing
  UnevaluatableError for this combination, ORM update statements
  will now fall back to "expire" when a concatenated JSON value used in a SET
  clause is to be synchronized to a Python object.

  References: #11849

• [orm] [bug] An warning is emitted if _orm.joinedload() or
  _orm.subqueryload() are used as a top level option against a
  statement that is not a SELECT statement, such as with an
  insert().returning(). There are no JOINs in INSERT statements nor is
  there a "subquery" that can be repurposed for subquery eager loading, and
  for UPDATE/DELETE joinedload does not support these either, so it is never
  appropriate for this use to pass silently.

  References: #11853

• [orm] [bug] Fixed issue where using loader options such as _orm.selectinload()
  with additional criteria in combination with ORM DML such as
  _sql.insert() with RETURNING would not correctly set up internal
  contexts required for caching to work correctly, leading to incorrect
  results.

  References: #11855

mysql

• [mysql] [bug] Fixed issue in mariadbconnector dialect where query string arguments that
  weren't checked integer or boolean arguments would be ignored, such as
  string arguments like unix_socket, etc. As part of this change, the
  argument parsing for particular elements such as client_flags,
  compress, local_infile has been made more consistent across all
  MySQL / MariaDB dialect which accept each argument. Pull request courtesy
  Tobias Alex-Petersen.

  References: #11870

sqlite

• [sqlite] [bug] [regression] The changes made for SQLite CHECK constraint reflection in versions 2.0.33
  and 2.0.34 , #11832 and #11677, have now been fully
  reverted, as users continued to identify existing use cases that stopped
  working after this change. For the moment, because SQLite does not
  provide any consistent way of delivering information about CHECK
  constraints, SQLAlchemy is limited in what CHECK constraint syntaxes can be
  reflected, including that a CHECK constraint must be stated all on a
  single, independent line (or inline on a column definition) without
  newlines, tabs in the constraint definition or unusual characters in the
  constraint name. Overall, reflection for SQLite is tailored towards being
  able to reflect CREATE TABLE statements that were originally created by
  SQLAlchemy DDL constructs. Long term work on a DDL parser that does not
  rely upon regular expressions may eventually improve upon this situation.
  A wide range of additional cross-dialect CHECK constraint reflection tests
  have been added as it was also a bug that these changes did not trip any
  existing tests.

  References: #11840