1.4.36

Released: April 26, 2022

orm

[orm] [bug] [regression] Fixed regression where the change made for #7861, released in
version 1.4.33, that brought the Insert construct to be partially
recognized as an ORM-enabled statement did not properly transfer the
correct mapper / mapped table state to the Session, causing the
Session.get_bind() method to fail for a Session that was
bound to engines and/or connections using the Session.binds
parameter.

References: #7936

[orm] [declarative] [bug] Modified the DeclarativeMeta metaclass to pass cls.__dict__
into the declarative scanning process to look for attributes, rather than
the separate dictionary passed to the type's __init__() method. This
allows user-defined base classes that add attributes within an
__init_subclass__() to work as expected, as __init_subclass__() can
only affect the cls.__dict__ itself and not the other dictionary. This
is technically a regression from 1.3 where __dict__ was being used.

References: #7900

[engine] [bug] Fixed a memory leak in the C extensions which could occur when calling upon
named members of Row when the member does not exist under Python
3; in particular this could occur during NumPy transformations when it
attempts to call members such as .__array__, but the issue was
surrounding any AttributeError thrown by the Row object. This
issue does not apply to version 2.0 which has already transitioned to
Cython. Thanks much to Sebastian Berg for identifying the problem.

References: #7875
[engine] [bug] Added a warning regarding a bug which exists in the Result.columns()
method when passing 0 for the index in conjunction with a Result
that will return a single ORM entity, which indicates that the current
behavior of Result.columns() is broken in this case as the
Result object will yield scalar values and not Row
objects. The issue will be fixed in 2.0, which would be a
backwards-incompatible change for code that relies on the current broken
behavior. Code which wants to receive a collection of scalar values should
use the Result.scalars() method, which will return a new
ScalarResult object that yields non-row scalar objects.

References: #7953

[schema] [bug] Fixed bug where ForeignKeyConstraint naming conventions using the
referred_column_0 naming convention key would not work if the foreign
key constraint were set up as a ForeignKey object rather than an
explicit ForeignKeyConstraint object. As this change makes use of
a backport of some fixes from version 2.0, an additional little-known
feature that has likely been broken for many years is also fixed which is
that a ForeignKey object may refer to a referred table by name of
the table alone without using a column name, if the name of the referent
column is the same as that of the referred column.

The referred_column_0 naming convention key was previously not tested
with the ForeignKey object, only ForeignKeyConstraint,
and this bug reveals that the feature has never worked correctly unless
ForeignKeyConstraint is used for all FK constraints. This bug
traces back to the original introduction of the feature introduced for
#3989.

References: #7958

[asyncio] [bug] Repaired handling of contextvar.ContextVar objects inside of async
adapted event handlers. Previously, values applied to a ContextVar
would not be propagated in the specific case of calling upon awaitables
inside of non-awaitable code.

References: #7937

[postgresql] [bug] Fixed bug in ARRAY datatype in combination with Enum on
PostgreSQL where using the .any() or .all() methods to render SQL
ANY() or ALL(), given members of the Python enumeration as arguments, would
produce a type adaptation failure on all drivers.

References: #6515
[postgresql] [bug] Implemented _postgresql.UUID.python_type attribute for the
PostgreSQL _postgresql.UUID type object. The attribute will return
either str or uuid.UUID based on the
_postgresql.UUID.as_uuid parameter setting. Previously, this
attribute was unimplemented. Pull request courtesy Alex Grönholm.

References: #7943
[postgresql] [bug] Fixed an issue in the psycopg2 dialect when using the
create_engine.pool_pre_ping parameter which would cause
user-configured AUTOCOMMIT isolation level to be inadvertently reset by
the "ping" handler.

References: #7930

[mysql] [bug] [regression] Fixed a regression in the untested MySQL PyODBC dialect caused by the fix
for #7518 in version 1.4.32 where an argument was being propagated
incorrectly upon first connect, leading to a TypeError.

References: #7871

[tests] [bug] For third party dialects, repaired a missing requirement for the
SimpleUpdateDeleteTest suite test which was not checking for a working
"rowcount" function on the target dialect.

References: #7919