1.4.41

Released: September 6, 2022

orm

• [orm] [bug] [events] Fixed event listening issue where event listeners added to a superclass
  would be lost if a subclass were created which then had its own listeners
  associated. The practical example is that of the sessionmaker
  class created after events have been associated with the
  _orm.Session class.

  References: #8467

• [orm] [bug] Hardened the cache key strategy for the _orm.aliased() and
  _orm.with_polymorphic() constructs. While no issue involving actual
  statements being cached can easily be demonstrated (if at all), these two
  constructs were not including enough of what makes them unique in their
  cache keys for caching on the aliased construct alone to be accurate.

  References: #8401

• [orm] [bug] [regression] Fixed regression appearing in the 1.4 series where a joined-inheritance
  query placed as a subquery within an enclosing query for that same entity
  would fail to render the JOIN correctly for the inner query. The issue
  manifested in two different ways prior and subsequent to version 1.4.18
  (related issue #6595), in one case rendering JOIN twice, in the
  other losing the JOIN entirely. To resolve, the conditions under which
  "polymorphic loading" are applied have been scaled back to not be invoked
  for simple joined inheritance queries.

  References: #8456

• [orm] [bug] Fixed issue in sqlalchemy.ext.mutable extension where collection
  links to the parent object would be lost if the object were merged with
  Session.merge() while also passing Session.merge.load
  as False.

  References: #8446

• [orm] [bug] Fixed issue involving _orm.with_loader_criteria() where a closure
  variable used as bound parameter value within the lambda would not carry
  forward correctly into additional relationship loaders such as
  _orm.selectinload() and _orm.lazyload() after the statement
  were cached, using the stale originally-cached value instead.

  References: #8399

sql

• [sql] [bug] Fixed issue where use of the _sql.table() construct, passing a string
  for the _sql.table.schema parameter, would fail to take the
  "schema" string into account when producing a cache key, thus leading to
  caching collisions if multiple, same-named _sql.table() constructs
  with different schemas were used.

  References: #8441

asyncio

• [asyncio] [bug] Integrated support for asyncpg's terminate() method call for cases
  where the connection pool is recycling a possibly timed-out connection,
  where a connection is being garbage collected that wasn't gracefully
  closed, as well as when the connection has been invalidated. This allows
  asyncpg to abandon the connection without waiting for a response that may
  incur long timeouts.

  References: #8419

mssql

• [mssql] [bug] [regression] Fixed regression caused by the fix for #8231 released in 1.4.40
  where connection would fail if the user did not have permission to query
  the dm_exec_sessions or dm_pdw_nodes_exec_sessions system views
  when trying to determine the current transaction isolation level.

  References: #8475