1.3.5

Released: June 17, 2019

• [bug] [mysql] Fixed bug where MySQL ON DUPLICATE KEY UPDATE would not accommodate setting
  a column to the value NULL. Pull request courtesy Lukáš Banič.

  References: #4715

• [bug] [orm] Fixed a series of related bugs regarding joined table inheritance more than
  two levels deep, in conjunction with modification to primary key values,
  where those primary key columns are also linked together in a foreign key
  relationship as is typical for joined table inheritance. The intermediary
  table in a three-level inheritance hierarchy will now get its UPDATE if
  only the primary key value has changed and passive_updates=False (e.g.
  foreign key constraints not being enforced), whereas before it would be
  skipped; similarly, with passive_updates=True (e.g. ON UPDATE CASCADE in
  effect), the third-level table will not receive an UPDATE statement as was
  the case earlier which would fail since CASCADE already modified it. In a
  related issue, a relationship linked to a three-level inheritance hierarchy
  on the primary key of an intermediary table of a joined-inheritance
  hierarchy will also correctly have its foreign key column updated when the
  parent object's primary key is modified, even if that parent object is a
  subclass of the linked parent class, whereas before these classes would
  not be counted.

  References: #4723

• [bug] [orm] Fixed bug where the Mapper.all_orm_descriptors accessor would
  return an entry for the Mapper itself under the declarative
  __mapper___ key, when this is not a descriptor. The .is_attribute
  flag that's present on all InspectionAttr objects is now
  consulted, which has also been modified to be True for an association
  proxy, as it was erroneously set to False for this object.

  References: #4729

• [bug] [orm] Fixed regression in Query.join() where the aliased=True flag
  would not properly apply clause adaptation to filter criteria, if a
  previous join were made to the same entity. This is because the adapters
  were placed in the wrong order. The order has been reversed so that the
  adapter for the most recent aliased=True call takes precedence as was
  the case in 1.2 and earlier. This broke the "elementtree" examples among
  other things.

  References: #4704

• [bug] [orm] [py3k] Replaced the Python compatbility routines for getfullargspec() with a
  fully vendored version from Python 3.3. Originally, Python was emitting
  deprecation warnings for this function in Python 3.8 alphas. While this
  change was reverted, it was observed that Python 3 implementations for
  getfullargspec() are an order of magnitude slower as of the 3.4 series
  where it was rewritten against Signature. While Python plans to
  improve upon this situation, SQLAlchemy projects for now are using a simple
  replacement to avoid any future issues.

  References: #4674

• [bug] [orm] Reworked the attribute mechanics used by AliasedClass to no
  longer rely upon calling __getattribute__ on the MRO of the wrapped
  class, and to instead resolve the attribute normally on the wrapped class
  using getattr(), and then unwrap/adapt that. This allows a greater range
  of attribute styles on the mapped class including special __getattr__()
  schemes; but it also makes the code simpler and more resilient in general.

  References: #4694

• [postgresql] [usecase] Added support for column sorting flags when reflecting indexes for
  PostgreSQL, including ASC, DESC, NULLSFIRST, NULLSLAST. Also adds this
  facility to the reflection system in general which can be applied to other
  dialects in future releases. Pull request courtesy Eli Collins.

  References: #4717

• [bug] [postgresql] Fixed bug where PostgreSQL dialect could not correctly reflect an ENUM
  datatype that has no members, returning a list with None for the
  get_enums() call and raising a TypeError when reflecting a column which
  has such a datatype. The inspection now returns an empty list.

  References: #4701

• [bug] [sql] Fixed a series of quoting issues which all stemmed from the concept of the
  literal_column() construct, which when being "proxied" through a
  subquery to be referred towards by a label that matches its text, the label
  would not have quoting rules applied to it, even if the string in the
  Label were set up as a quoted_name construct. Not
  applying quoting to the text of the Label is a bug because this
  text is strictly a SQL identifier name and not a SQL expression, and the
  string should not have quotes embedded into it already unlike the
  literal_column() which it may be applied towards. The existing
  behavior of a non-labeled literal_column() being propagated as is on
  the outside of a subquery is maintained in order to help with manual
  quoting schemes, although it's not clear if valid SQL can be generated for
  such a construct in any case.

  References: #4730