Released: July 21, 2019
[bug] [engine] Fixed bug where using reflection function such as
Engineobject that had execution options applied to it
would fail, as the resulting
OptionEngineproxy object failed to
.engineattribute used within the reflection routines.
[bug] [mysql] Fixed bug where the special logic to render "NULL" for the
nullable=Truewould not work if the
column's datatype were a
The logic now ensures that it unwraps down to the original
TIMESTAMPso that this special case NULL keyword is correctly
rendered when requested.
[orm] [performance] The optimization applied to selectin loading in #4340 where a JOIN
is not needed to eagerly load related items is now applied to many-to-one
relationships as well, so that only the related table is queried for a
simple join condition. In this case, the related items are queried
based on the value of a foreign key column on the parent; if these columns
are deferred or otherwise not loaded on any of the parent objects in
the collection, the loader falls back to the JOIN method.
[bug] [orm] Fixed regression caused by #4365 where a join from an entity to
itself without using aliases no longer raises an informative error message,
instead failing on an assertion. The informative error condition has been
[feature] [orm] Added new loader option method
Load.options()which allows loader
options to be constructed hierarchically, so that many sub-options can be
applied to a particular path without needing to call
many times. Thanks to Alessio Bogon for the idea.
[postgresql] [usecase] Added support for reflection of indexes on PostgreSQL partitioned tables,
which was added to PostgreSQL as of version 11.
[bug] [mysql] Enhanced MySQL/MariaDB version string parsing to accommodate for exotic
MariaDB version strings where the "MariaDB" word is embedded among other
alphanumeric characters such as "MariaDBV1". This detection is critical in
order to correctly accommodate for API features that have split between MySQL
and MariaDB such as the "transaction_isolation" system variable.
[bug] [mssql] Ensured that the queries used to reflect indexes and view definitions will
explicitly CAST string parameters into NVARCHAR, as many SQL Server drivers
frequently treat string values, particularly those with non-ascii
characters or larger string values, as TEXT which often don't compare
correctly against VARCHAR characters in SQL Server's information schema
tables for some reason. These CAST operations already take place for
reflection queries against SQL Server
were missing from three additional queries that are against
[bug] [orm] Fixed an issue where the
orm._ORMJoin.join()method, which is a
not-internally-used ORM-level method that exposes what is normally an
internal process of
Query.join(), did not propagate the
outerjoinkeyword arguments correctly. Pull request courtesy Denis
[bug] [sql] Adjusted the initialization for
Enumto minimize how often it
.__members__attribute of a given PEP-435 enumeration
object, to suit the case where this attribute is expensive to invoke, as is
the case for some popular third party enumeration libraries.
[bug] [orm] Fixed bug where a many-to-one relationship that specified
would fail to update correctly during a primary key change where a related
column needs to change.
[bug] [orm] Fixed bug where the detection for many-to-one or one-to-one use with a
"dynamic" relationship, which is an invalid configuration, would fail to
raise if the relationship were configured with
current fix is that it warns, instead of raises, as this would otherwise be
backwards incompatible, however in a future release it will be a raise.
[bug] [orm] Fixed bug where a synonym created against a mapped attribute that does not
exist yet, as is the case when it refers to backref before mappers are
configured, would raise recursion errors when trying to test for attributes
on it which ultimately don't exist (as occurs when the classes are run
through Sphinx autodoc), as the unconfigured state of the synonym would put
it into an attribute not found loop.
[postgresql] [usecase] Added support for multidimensional Postgresql array literals via nesting
postgresql.arrayobject within another one. The
multidimensional array type is detected automatically.
[bug] [postgresql] [sql] Fixed issue where the
array_aggconstruct in combination with
FunctionElement.filter()would not produce the correct operator
precedence in combination with the array index operator.
[bug] [sql] Fixed an unlikely issue where the "corresponding column" routine for unions
CompoundSelectobjects could return the wrong column in
some overlapping column situtations, thus potentially impacting some ORM
operations when set operations are in use, if the underlying
select()constructs were used previously in other similar kinds of
routines, due to a cached value not being cleared.
[sqlite] [usecase] Added support for composite (tuple) IN operators with SQLite, by rendering
the VALUES keyword for this backend. As other backends such as DB2 are
known to use the same syntax, the syntax is enabled in the base compiler
using a dialect-level flag
tuple_in_values. The change also includes
support for "empty IN tuple" expressions for SQLite when using "in_()"
between a tuple value and an empty set.