Changelog
### 1.4.27
```
:include_notes_from: unreleased_14
.. changelog::
```
### 1.4.26
```
:released: October 19, 2021
.. change::
:tags: orm
:tickets: 6284
Passing a :class:`.Query` object to :meth:`_orm.Session.execute` is not
the intended use of this object, and will now raise a deprecation warning.
.. change::
:tags: bug, postgresql
:tickets: 5387
Added a "disconnect" condition for the "SSL SYSCALL error: Bad address"
error message as reported by psycopg2. Pull request courtesy Zeke Brechtel.
.. change::
:tags: bug, orm
Improved the exception message generated when configuring a mapping with
joined table inheritance where the two tables either have no foreign key
relationships set up, or where they have multiple foreign key relationships
set up. The message is now ORM specific and includes context that the
:paramref:`_orm.Mapper.inherit_condition` parameter may be needed
particularly for the ambiguous foreign keys case.
.. change::
:tags: bug, sql
:tickets: 6520
Fixed issue where SQL queries using the
:meth:`_functions.FunctionElement.within_group` construct could not be
pickled, typically when using the ``sqlalchemy.ext.serializer`` extension
but also for general generic pickling.
.. change::
:tags: bug, orm
:tickets: 7189
Fixed issue with :func:`_orm.with_loader_criteria` feature where ON
criteria would not be added to a JOIN for a query of the form
``select(A).join(B)``, stating a target while making use of an implicit
ON clause.
.. change::
:tags: bug, orm
:tickets: 7205
Fixed bug where the ORM "plugin", necessary for features such as
:func:`_orm.with_loader_criteria` to work correctly, would not be applied
to a :func:`_sql.select` which queried from an ORM column expression if it
made use of the :meth:`_sql.ColumnElement.label` modifier.
.. change::
:tags: bug, mypy
:tickets: 6435
Fixed issue in mypy plugin to improve upon some issues detecting ``Enum()``
SQL types containing custom Python enumeration classes. Pull request
courtesy Hiroshi Ogawa.
.. change::
:tags: bug, mysql
:tickets: 7144
Fixed issue in MySQL :func:`_mysql.match` construct where passing a clause
expression such as :func:`_sql.bindparam` or other SQL expression for the
"against" parameter would fail. Pull request courtesy Anton Kovalevich.
.. change::
:tags: bug, mssql
:tickets: 7160
Fixed issue with :meth:`.Inspector.get_foreign_keys` where foreign
keys were omitted if they were established against a unique
index instead of a unique constraint.
.. change::
:tags: usecase, mssql
Added reflection support for SQL Server foreign key options, including
"ON UPDATE" and "ON DELETE" values of "CASCADE" and "SET NULL".
.. change::
:tags: bug, sql
:tickets: 4123
Repaired issue in new :paramref:`_sql.HasCTE.cte.nesting` parameter
introduced with :ticket:`4123` where a recursive :class:`_sql.CTE` using
:paramref:`_sql.HasCTE.cte.recursive` in typical conjunction with UNION
would not compile correctly. Additionally makes some adjustments so that
the :class:`_sql.CTE` construct creates a correct cache key.
Pull request courtesy Eric Masseran.
.. change::
:tags: bug, engine
:tickets: 7130
Fixed issue where the deprecation warning for the :class:`.URL` constructor
which indicates that the :meth:`.URL.create` method should be used would
not emit if a full positional argument list of seven arguments were passed;
additionally, validation of URL arguments will now occur if the constructor
is called in this way, which was being skipped previously.
.. change::
:tags: bug, orm
:tickets: 7103
Add missing methods added in :ticket:`6991` to
:class:`_scoping.scoped_session` and :func:`_asyncio.async_scoped_session`.
.. change::
:tags: bug, examples
:tickets: 7169
Repaired the examples in examples/versioned_rows to use SQLAlchemy 1.4 APIs
correctly; these examples had been missed when API changes like removing
"passive" from :meth:`_orm.Session.is_modified` were made as well as the
:meth:`_ormevents.SessionEvents.do_orm_execute()` event hook were added.
.. change::
:tags: bug, orm
:tickets: 6974, 6972
An extra layer of warning messages has been added to the functionality
of :meth:`_orm.Query.join` and the ORM version of
:meth:`_sql.Select.join`, where a few places where "automatic aliasing"
continues to occur will now be called out as a pattern to avoid, mostly
specific to the area of joined table inheritance where classes that share
common base tables are being joined together without using explicit aliases.
One case emits a legacy warning for a pattern that's not recommended,
the other case is fully deprecated.
The automatic aliasing within ORM join() which occurs for overlapping
mapped tables does not work consistently with all APIs such as
:func:`_orm.contains_eager()`, and rather than continue to try to make
these use cases work everywhere, replacing with a more user-explicit
pattern is clearer, less prone to bugs and simplifies SQLAlchemy's
internals further.
The warnings include links to the errors.rst page where each pattern is
demonstrated along with the recommended pattern to fix.
.. seealso::
:ref:`error_xaj1`
:ref:`error_xaj2`
.. change::
:tags: bug, sql
:tickets: 7061
Account for the :paramref:`_sql.table.schema` parameter passed to
the :func:`_sql.table` construct, such that it is taken into account
when accessing the :attr:`_sql.TableClause.fullname` attribute.
.. change::
:tags: bug, sql
:tickets: 7140
Fixed an inconsistency in the :meth:`_sql.ColumnOperators.any_` /
:meth:`_sql.ColumnOperators.all_` functions / methods where the special
behavior these functions have of "flipping" the expression such that the
"ANY" / "ALL" expression is always on the right side would not function if
the comparison were against the None value, that is, "column.any_() ==
None" should produce the same SQL expression as "null() == column.any_()".
Added more docs to clarify this as well, plus mentions that any_() / all_()
generally supersede the ARRAY version "any()" / "all()".
.. change::
:tags: engine, bug, postgresql
:tickets: 3247
The :meth:`_reflection.Inspector.reflect_table` method now supports
reflecting tables that do not have user defined columns. This allows
:meth:`_schema.MetaData.reflect` to properly complete reflection on
databases that contain such tables. Currently, only PostgreSQL is known to
support such a construct among the common database backends.
.. change::
:tags: sql, bug, regression
:tickets: 7177
Fixed issue where "expanding IN" would fail to function correctly with
datatypes that use the :meth:`_types.TypeEngine.bind_expression` method,
where the method would need to be applied to each element of the
IN expression rather than the overall IN expression itself.
.. change::
:tags: postgresql, bug, regression
:tickets: 7177
Fixed issue where IN expressions against a series of array elements, as can
be done with PostgreSQL, would fail to function correctly due to multiple
issues within the "expanding IN" feature of SQLAlchemy Core that was
standardized in version 1.4. The psycopg2 dialect now makes use of the
:meth:`_types.TypeEngine.bind_expression` method with :class:`_types.ARRAY`
to portably apply the correct casts to elements. The asyncpg dialect was
not affected by this issue as it applies bind-level casts at the driver
level rather than at the compiler level.
.. change::
:tags: bug, mysql
:tickets: 7204
Fixed installation issue where the ``sqlalchemy.dialects.mysql`` module
would not be importable if "greenlet" were not installed.
.. change::
:tags: bug, mssql
:tickets: 7168
Fixed issue with :meth:`.Inspector.has_table` where it would return False
if a local temp table with the same name from a different session happened
to be returned first when querying tempdb. This is a continuation of
:ticket:`6910` which accounted for the temp table existing only in the
alternate session and not the current one.
.. change::
:tags: bug, orm
:tickets: 7128
Fixed bug where iterating a :class:`.Result` from a :class:`_orm.Session`
after that :class:`_orm.Session` were closed would partially attach objects
to that session in an essentially invalid state. It now raises an exception
with a link to new documentation if an **un-buffered** result is iterated
from a :class:`_orm.Session` that was closed or otherwise had the
:meth:`_orm.Session.expunge_all` method called after that :class:`.Result`
was generated. The ``prebuffer_rows`` execution option, as is used
automatically by the asyncio extension for client-side result sets, may be
used to produce a :class:`.Result` where the ORM objects are prebuffered,
and in this case iterating the result will produce a series of detached
objects.
.. seealso::
:ref:`error_lkrp`
.. change::
:tags: bug, mssql, regression
:tickets: 7129
Fixed bug in SQL Server :class:`_mssql.DATETIMEOFFSET` datatype where the
ODBC implementation would not generate the correct DDL, for cases where the
type were converted using the ``dialect.type_descriptor()`` method, the
usage of which is illustrated in some documented examples for
:class:`.TypeDecorator`, though not necessary for most datatypes.
Regression was introduced by :ticket:`6366`. As part of this change, the
full list of SQL Server date types have been amended to return a "dialect
impl" that generates the same DDL name as the supertype.
.. change::
:tags: bug, sql
:tickets: 7153
Adjusted the "column disambiguation" logic that's new in 1.4, where the
same expression repeated gets an "extra anonymous" label, so that the logic
more aggressively deduplicates those labels when the repeated element
is the same Python expression object each time, as occurs in cases like
when using "singleton" values like :func:`_sql.null`. This is based on
the observation that at least some databases (e.g. MySQL, but not SQLite)
will raise an error if the same label is repeated inside of a subquery.
.. change::
:tags: bug, orm
:tickets: 7154
Related to :ticket:`7153`, fixed an issue where result column lookups would
fail for "adapted" SELECT statements that selected for "constant" value
expressions most typically the NULL expression, as would occur in such
places as joined eager loading in conjunction with limit/offset. This was
overall a regression due to issue :ticket:`6259` which removed all
"adaption" for constants like NULL, "true", and "false" when rewriting
expressions in a SQL statement, but this broke the case where the same
adaption logic were used to resolve the constant to a labeled expression
for the purposes of result set targeting.
.. change::
:tags: bug, orm, regression
:tickets: 7134
Fixed regression where ORM loaded objects could not be pickled in cases
where loader options making use of ``"*"`` were used in certain
combinations, such as combining the :func:`_orm.joinedload` loader strategy
with ``raiseload('*')`` of sub-elements.
.. change::
:tags: bug, engine
:tickets: 7077
Implemented proper ``__reduce__()`` methods for all SQLAlchemy exception
objects to ensure they all support clean round trips when pickling, as
exception objects are often serialized for the purposes of various
debugging tools.
.. change::
:tags: bug, orm, regression
:tickets: 7209
Fixed regression where the use of a :class:`_hybrid.hybrid_property`
attribute or a mapped :func:`_orm.composite` attribute as a key passed to
the :meth:`_dml.Update.values` method for an ORM-enabled
:class:`_dml.Update` statement, as well as when using it via the legacy
:meth:`_orm.Query.update` method, would be processed for incoming
ORM/hybrid/composite values within the compilation stage of the UPDATE
statement, which meant that in those cases where caching occurred,
subsequent invocations of the same statement would no longer receive the
correct values. This would include not only hybrids that use the
:meth:`_hybrid.hybrid_property.update_expression` method, but any use of a
plain hybrid attribute as well. For composites, the issue instead caused a
non-repeatable cache key to be generated, which would break caching and
could fill up the statement cache with repeated statements.
The :class:`_dml.Update` construct now handles the processing of key/value
pairs passed to :meth:`_dml.Update.values` and
:meth:`_dml.Update.ordered_values` up front when the construct is first
generated, before the cache key has been generated so that the key/value
pairs are processed each time, and so that the cache key is generated
against the individual column/value pairs that will ultimately be
used in the statement.
.. changelog::
```
### 1.4.25
```
:released: September 22, 2021
.. change::
:tags: bug, platform, regression
:tickets: 7024
Fixed regression due to :ticket:`7024` where the reorganization of the
"platform machine" names used by the ``greenlet`` dependency mis-spelled
"aarch64" and additionally omitted uppercase "AMD64" as is needed for
Windows machines. Pull request courtesy James Dow.
.. changelog::
```
### 1.4.24
```
:released: September 22, 2021
.. change::
:tags: bug, asyncio
:tickets: 6943
Fixed a bug in :meth:`_asyncio.AsyncSession.execute` and
:meth:`_asyncio.AsyncSession.stream` that required ``execution_options``
to be an instance of ``immutabledict`` when defined. It now
correctly accepts any mapping.
.. change::
:tags: engine, asyncio, usecase
:tickets: 6832
Improve the interface used by adapted drivers, like the asyncio ones,
to access the actual connection object returned by the driver.
The :class:`._ConnectionFairy` object has two new attributes:
* :attr:`._ConnectionFairy.dbapi_connection` always represents a DBAPI
compatible object. For pep-249 drivers, this is the DBAPI connection as
it always has been, previously accessed under the ``.connection``
attribute. For asyncio drivers that SQLAlchemy adapts into a pep-249
interface, the returned object will normally be a SQLAlchemy adaption
object called :class:`_engine.AdaptedConnection`.
* :attr:`._ConnectionFairy.driver_connection` always represents the actual
connection object maintained by the third party pep-249 DBAPI or async
driver in use. For standard pep-249 DBAPIs, this will always be the same
object as that of the ``dbapi_connection``. For an asyncio driver, it
will be the underlying asyncio-only connection object.
The ``.connection`` attribute remains available and is now a legacy alias
of ``.dbapi_connection``.
.. seealso::
:ref:`faq_dbapi_connection`
.. change::
:tags: bug, sql
:tickets: 7052
Implemented missing methods in :class:`_functions.FunctionElement` which,
while unused, would lead pylint to report them as unimplemented abstract
methods.
.. change::
:tags: bug, mssql, reflection
:tickets: 6910
Fixed an issue where :meth:`_reflection.has_table` returned
``True`` for local temporary tables that actually belonged to a
different SQL Server session (connection). An extra check is now
performed to ensure that the temp table detected is in fact owned
by the current session.
.. change::
:tags: bug, engine, regression
:tickets: 6913
Fixed issue where the ability of the
:meth:`_events.ConnectionEvents.before_execute` method to alter the SQL
statement object passed, returning the new object to be invoked, was
inadvertently removed. This behavior has been restored.
.. change::
:tags: bug, engine
:tickets: 6958
Ensure that ``str()`` is called on the an
:paramref:`_url.URL.create.password` argument, allowing usage of objects
that implement the ``__str__()`` method as password attributes. Also
clarified that one such object is not appropriate to dynamically change the
password for each database connection; the approaches at
:ref:`engines_dynamic_tokens` should be used instead.
.. change::
:tags: bug, orm, regression
:tickets: 6979
Fixed ORM issue where column expressions passed to ``query()`` or
ORM-enabled ``select()`` would be deduplicated on the identity of the
object, such as a phrase like ``select(A.id, null(), null())`` would
produce only one "NULL" expression, which previously was not the case in
1.3. However, the change also allows for ORM expressions to render as given
as well, such as ``select(A.data, A.data)`` will produce a result row with
two columns.
.. change::
:tags: bug, engine
:tickets: 6983
Fixed issue in :class:`_engine.URL` where validation of "drivername" would
not appropriately respond to the ``None`` value where a string were
expected.
.. change::
:tags: bug, mypy
:tickets: 6950
Fixed issue where mypy plugin would crash when interpreting a
``query_expression()`` construct.
.. change::
:tags: usecase, sql
:tickets: 4123
Added new parameter :paramref:`_sql.HasCTE.cte.nesting` to the
:class:`_sql.CTE` constructor and :meth:`_sql.HasCTE.cte` method, which
flags the CTE as one which should remain nested within an enclosing CTE,
rather than being moved to the top level of the outermost SELECT. While in
the vast majority of cases there is no difference in SQL functionality,
users have identified various edge-cases where true nesting of CTE
constructs is desirable. Much thanks to Eric Masseran for lots of work on
this intricate feature.
.. change::
:tags: usecase, engine, orm
:tickets: 6990
Added new methods :meth:`_orm.Session.scalars`,
:meth:`_engine.Connection.scalars`, :meth:`_asyncio.AsyncSession.scalars`
and :meth:`_asyncio.AsyncSession.stream_scalars`, which provide a short cut
to the use case of receiving a row-oriented :class:`_result.Result` object
and converting it to a :class:`_result.ScalarResult` object via the
:meth:`_engine.Result.scalars` method, to return a list of values rather
than a list of rows. The new methods are analogous to the long existing
:meth:`_orm.Session.scalar` and :meth:`_engine.Connection.scalar` methods
used to return a single value from the first row only. Pull request
courtesy Miguel Grinberg.
.. change::
:tags: usecase, orm
:tickets: 6955
Added loader options to :meth:`_orm.Session.merge` and
:meth:`_asyncio.AsyncSession.merge` via a new
:paramref:`_orm.Session.merge.options` parameter, which will apply the
given loader options to the ``get()`` used internally by merge, allowing
eager loading of relationships etc. to be applied when the merge process
loads a new object. Pull request courtesy Daniel Stone.
.. change::
:tags: feature, asyncio, mysql
:tickets: 6993
Added initial support for the ``asyncmy`` asyncio database driver for MySQL
and MariaDB. This driver is very new, however appears to be the only
current alternative to the ``aiomysql`` driver which currently appears to
be unmaintained and is not working with current Python versions. Much
thanks to long2ice for the pull request for this dialect.
.. seealso::
:ref:`asyncmy`
.. change::
:tags: bug, asyncio
Added missing ``**kw`` arguments to the
:meth:`_asyncio.AsyncSession.connection` method.
.. change::
:tags: bug, sql
:tickets: 7055
Fixed a two issues where combinations of ``select()`` and ``join()`` when
adapted to form a copy of the element would not completely copy the state
of all column objects associated with subqueries. A key problem this caused
is that usage of the :meth:`_sql.ClauseElement.params` method (which should
probably be moved into a legacy category as it is inefficient and error
prone) would leave copies of the old :class:`_sql.BindParameter` objects
around, leading to issues in correctly setting the parameters at execution
time.
.. change::
:tags: bug, orm, regression
:tickets: 6924
Fixed issue in recently repaired ``Query.with_entities()`` method where the
flag that determines automatic uniquing for legacy ORM ``Query`` objects
only would be set to ``True`` inappropriately in cases where the
``with_entities()`` call would be setting the ``Query`` to return
column-only rows, which are not uniqued.
.. change::
:tags: bug, postgresql
:tickets: 6912
Qualify ``version()`` call to avoid shadowing issues if a different
search path is configured by the user.
.. change::
:tags: bug, engine, postgresql
:tickets: 6963
Fixed issue where an engine that had
:paramref:`_sa.create_engine.implicit_returning` set to False would fail to
function when PostgreSQL's "fast insertmany" feature were used in
conjunction with a ``Sequence``, as well as if any kind of "executemany"
with "return_defaults()" were used in conjunction with a ``Sequence``. Note
that PostgreSQL "fast insertmany" uses "RETURNING" by definition, when the
SQL statement is passed to the driver; overall, the
:paramref:`_sa.create_engine.implicit_returning` flag is legacy and has no
real use in modern SQLAlchemy, and will be deprecated in a separate change.
.. change::
:tags: bug, mypy
:tickets: 6937
Fixed issue in mypy plugin where columns on a mixin would not be correctly
interpreted if the mapped class relied upon a ``__tablename__`` routine
that came from a superclass.
.. change::
:tags: bug, postgresql
:tickets: 6106
The :class:`_postgresql.ENUM` datatype is PostgreSQL-native and therefore
should not be used with the ``native_enum=False`` flag. This flag is now
ignored if passed to the :class:`_postgresql.ENUM` datatype and a warning
is emitted; previously the flag would cause the type object to fail to
function correctly.
.. change::
:tags: bug, sql
:tickets: 7036
Fixed issue related to new :meth:`_sql.HasCTE.add_cte` feature where
pairing two "INSERT..FROM SELECT" statements simultaneously would lose
track of the two independent SELECT statements, leading to the wrong SQL.
.. change::
:tags: asyncio, bug
:tickets: 6746
Deprecate usage of :class:`_orm.scoped_session` with asyncio drivers. When
using Asyncio the :class:`_asyncio.async_scoped_session` should be used
instead.
.. change::
:tags: bug, platform
:tickets: 7024
Further adjusted the "greenlet" package specifier in setup.cfg to use a
long chain of "or" expressions, so that the comparison of
``platform_machine`` to a specific identifier matches only the complete
string.
.. change::
:tags: bug, sqlite
Fixed bug where the error message for SQLite invalid isolation level on the
pysqlite driver would fail to indicate that "AUTOCOMMIT" is one of the
valid isolation levels.
.. change::
:tags: bug, sql
:tickets: 7060
Fixed issue where using ORM column expressions as keys in the list of
dictionaries passed to :meth:`_sql.Insert.values` for "multi-valued insert"
would not be processed correctly into the correct column expressions.
.. change::
:tags: asyncio, usecase
:tickets: 6746
The :class:`_asyncio.AsyncSession` now supports overriding which
:class:`_orm.Session` it uses as the proxied instance. A custom ``Session``
class can be passed using the :paramref:`.AsyncSession.sync_session_class`
parameter or by subclassing the ``AsyncSession`` and specifying a custom
:attr:`.AsyncSession.sync_session_class`.
.. change::
:tags: bug, oracle, performance
:tickets: 4486
Added a CAST(VARCHAR2(128)) to the "table name", "owner", and other
DDL-name parameters as used in reflection queries against Oracle system
views such as ALL_TABLES, ALL_TAB_CONSTRAINTS, etc to better enable
indexing to take place against these columns, as they previously would be
implicitly handled as NVARCHAR2 due to Python's use of Unicode for strings;
these columns are documented in all Oracle versions as being VARCHAR2 with
lengths varying from 30 to 128 characters depending on server version.
Additionally, test support has been enabled for Unicode-named DDL
structures against Oracle databases.
.. changelog::
```
### 1.4.23
```
:released: August 18, 2021
.. change::
:tags: bug, sql
:tickets: 6752
Fix issue in :class:`_sql.CTE` where new :meth:`_sql.HasCTE.add_cte` method
added in version 1.4.21 / :ticket:`6752` failed to function correctly for
"compound select" structures such as :func:`_sql.union`,
:func:`_sql.union_all`, :func:`_sql.except`, etc. Pull request courtesy
Eric Masseran.
.. change::
:tags: orm, usecase
:tickets: 6808
Added new attribute :attr:`_sql.Select.columns_clause_froms` that will
retrieve the FROM list implied by the columns clause of the
:class:`_sql.Select` statement. This differs from the old
:attr:`_sql.Select.froms` collection in that it does not perform any ORM
compilation steps, which necessarily deannotate the FROM elements and do
things like compute joinedloads etc., which makes it not an appropriate
candidate for the :meth:`_sql.Select.select_from` method. Additionally adds
a new parameter
:paramref:`_sql.Select.with_only_columns.maintain_column_froms` that
transfers this collection to :meth:`_sql.Select.select_from` before
replacing the columns collection.
In addition, the :attr:`_sql.Select.froms` is renamed to
:meth:`_sql.Select.get_final_froms`, to stress that this collection is not
a simple accessor and is instead calculated given the full state of the
object, which can be an expensive call when used in an ORM context.
Additionally fixes a regression involving the
:func:`_orm.with_only_columns` function to support applying criteria to
column elements that were replaced with either
:meth:`_sql.Select.with_only_columns` or :meth:`_orm.Query.with_entities` ,
which had broken as part of :ticket:`6503` released in 1.4.19.
.. change::
:tags: bug, orm, sql
:tickets: 6824
Fixed issue where a bound parameter object that was "cloned" would cause a
name conflict in the compiler, if more than one clone of this parameter
were used at the same time in a single statement. This could occur in
particular with things like ORM single table inheritance queries that
indicated the same "discriminator" value multiple times in one query.
.. change::
:tags: bug, mssql, sql
:tickets: 6863
Fixed issue where the ``literal_binds`` compiler flag, as used externally
to render bound parameters inline, would fail to work when used with a
certain class of parameters known as "literal_execute", which covers things
like LIMIT and OFFSET values for dialects where the drivers don't allow a
bound parameter, such as SQL Server's "TOP" clause. The issue locally
seemed to affect only the MSSQL dialect.
.. change::
:tags: bug, orm
:tickets: 6869
Fixed issue in loader strategies where the use of the
:meth:`_orm.Load.options` method, particularly when nesting multiple calls,
would generate an overly long and more importantly non-deterministic cache
key, leading to very large cache keys which were also not allowing
efficient cache usage, both in terms of total memory used as well as number
of entries used in the cache itself.
.. change::
:tags: bug, sql
:tickets: 6858
Fixed an issue in the ``CacheKey.to_offline_string()`` method used by the
dogpile.caching example where attempting to create a proper cache key from
the special "lambda" query generated by the lazy loader would fail to
include the parameter values, leading to an incorrect cache key.
.. change::
:tags: bug, orm
:tickets: 6887
Revised the means by which the
:attr:`_orm.ORMExecuteState.user_defined_options` accessor receives
:class:`_orm.UserDefinedOption` and related option objects from the
context, with particular emphasis on the "selectinload" on the loader
strategy where this previously was not working; other strategies did not
have this problem. The objects that are associated with the current query
being executed, and not that of a query being cached, are now propagated
unconditionally. This essentially separates them out from the "loader
strategy" options which are explicitly associated with the compiled state
of a query and need to be used in relation to the cached query.
The effect of this fix is that a user-defined option, such as those used
by the dogpile.caching example as well as for other recipes such as
defining a "shard id" for the horizontal sharing extension, will be
correctly propagated to eager and lazy loaders regardless of whether
a cached query was ultimately invoked.
.. change::
:tags: bug, sql
:tickets: 6886
Adjusted the "from linter" warning feature to accommodate for a chain of
joins more than one level deep where the ON clauses don't explicitly match
up the targets, such as an expression such as "ON TRUE". This mode of use
is intended to cancel the cartesian product warning simply by the fact that
there's a JOIN from "a to b", which was not working for the case where the
chain of joins had more than one element.
.. change::
:tags: bug, postgresql
:tickets: 6886
Added the "is_comparison" flag to the PostgreSQL "overlaps",
"contained_by", "contains" operators, so that they work in relevant ORM
contexts as well as in conjunction with the "from linter" feature.
.. change::
:tags: bug, orm
:tickets: 6812
Fixed issue where the unit of work would internally use a 2.0-deprecated
SQL expression form, emitting a deprecation warning when SQLALCHEMY_WARN_20
were enabled.
.. change::
:tags: bug, orm
:tickets: 6881
Fixed issue in :func:`_orm.selectinload` where use of the new
:meth:`_orm.PropComparator.and_` feature within options that were nested
more than one level deep would fail to update bound parameter values that
were in the nested criteria, as a side effect of SQL statement caching.
.. change::
:tags: bug, general
:tickets: 6136
The setup requirements have been modified such ``greenlet`` is a default
requirement only for those platforms that are well known for ``greenlet``
to be installable and for which there is already a pre-built binary on
pypi; the current list is ``x86_64 aarch64 ppc64le amd64 win32``. For other
platforms, greenlet will not install by default, which should enable
installation and test suite running of SQLAlchemy 1.4 on platforms that
don't support ``greenlet``, excluding any asyncio features. In order to
install with the ``greenlet`` dependency included on a machine architecture
outside of the above list, the ``[asyncio]`` extra may be included by
running ``pip install sqlalchemy[asyncio]`` which will then attempt to
install ``greenlet``.
Additionally, the test suite has been repaired so that tests can complete
fully when greenlet is not installed, with appropriate skips for
asyncio-related tests.
.. change::
:tags: enum, schema
:tickets: 6146
Unify behaviour :class:`_schema.Enum` in native and non-native
implementations regarding the accepted values for an enum with
aliased elements.
When :paramref:`_schema.Enum.omit_aliases` is ``False`` all values,
alias included, are accepted as valid values.
When :paramref:`_schema.Enum.omit_aliases` is ``True`` only non aliased values
are accepted as valid values.
.. change::
:tags: bug, ext
:tickets: 6816
Fixed issue where the horizontal sharding extension would not correctly
accommodate for a plain textual SQL statement passed to
:meth:`_orm.Session.execute`.
.. change::
:tags: bug, orm
:tickets: 6889, 6079
Adjusted ORM loader internals to no longer use the "lambda caching" system
that was added in 1.4, as well as repaired one location that was still
using the previous "baked query" system for a query. The lambda caching
system remains an effective way to reduce the overhead of building up
queries that have relatively fixed usage patterns. In the case of loader
strategies, the queries used are responsible for moving through lots of
arbitrary options and criteria, which is both generated and sometimes
consumed by end-user code, that make the lambda cache concept not any more
efficient than not using it, at the cost of more complexity. In particular
the problems noted by :ticket:`6881` and :ticket:`6887` are made are made
considerably less complicated by removing this feature internally.
.. change::
:tags: bug, orm
:tickets: 6889
Fixed an issue where the :class:`_orm.Bundle` construct would not create
proper cache keys, leading to inefficient use of the query cache. This
had some impact on the "selectinload" strategy and was identified as
part of :ticket:`6889`.
.. change::
:tags: usecase, mypy
:tickets: 6804, 6759
Added support for SQLAlchemy classes to be defined in user code using
"generic class" syntax as defined by ``sqlalchemy2-stubs``, e.g.
``Column[String]``, without the need for qualifying these constructs within
a ``TYPE_CHECKING`` block by implementing the Python special method
``__class_getitem__()``, which allows this syntax to pass without error at
runtime.
.. change::
:tags: bug, sql
Fixed issue in lambda caching system where an element of a query that
produces no cache key, like a custom option or clause element, would still
populate the expression in the "lambda cache" inappropriately.
.. changelog::
```
### 1.4.22
```
:released: July 21, 2021
.. change::
:tags: bug, sql
:tickets: 6786
Fixed issue where use of the :paramref:`_sql.case.whens` parameter passing
a dictionary positionally and not as a keyword argument would emit a 2.0
deprecation warning, referring to the deprecation of passing a list
positionally. The dictionary format of "whens", passed positionally, is
still supported and was accidentally marked as deprecated.
.. change::
:tags: bug, orm
:tickets: 6775
Fixed issue in new :meth:`_schema.Table.table_valued` method where the
resulting :class:`_sql.TableValuedColumn` construct would not respond
correctly to alias adaptation as is used throughout the ORM, such as for
eager loading, polymorphic loading, etc.
.. change::
:tags: bug, orm
:tickets: 6769
Fixed issue where usage of the :meth:`_result.Result.unique` method with an
ORM result that included column expressions with unhashable types, such as
``JSON`` or ``ARRAY`` using non-tuples would silently fall back to using
the ``id()`` function, rather than raising an error. This now raises an
error when the :meth:`_result.Result.unique` method is used in a 2.0 style
ORM query. Additionally, hashability is assumed to be True for result
values of unknown type, such as often happens when using SQL functions of
unknown return type; if values are truly not hashable then the ``hash()``
itself will raise.
For legacy ORM queries, since the legacy :class:`_orm.Query` object
uniquifies in all cases, the old rules remain in place, which is to use
``id()`` for result values of unknown type as this legacy uniquing is
mostly for the purpose of uniquing ORM entities and not column values.
.. change::
:tags: orm, bug
:tickets: 6771
Fixed an issue where clearing of mappers during things like test suite
teardowns could cause a "dictionary changed size" warning during garbage
collection, due to iteration of a weak-referencing dictionary. A ``list()``
has been applied to prevent concurrent GC from affecting this operation.
.. change::
:tags: bug, sql
:tickets: 6770
Fixed issue where type-specific bound parameter handlers would not be
called upon in the case of using the :meth:`_sql.Insert.values` method with
the Python ``None`` value; in particular, this would be noticed when using
the :class:`_types.JSON` datatype as well as related PostgreSQL specific
types such as :class:`_postgresql.JSONB` which would fail to encode the
Python ``None`` value into JSON null, however the issue was generalized to
any bound parameter handler in conjunction with this specific method of
:class:`_sql.Insert`.
.. change::
:tags: bug, engine
:tickets: 6740
Added some guards against ``KeyError`` in the event system to accommodate
the case that the interpreter is shutting down at the same time
:meth:`_engine.Engine.dispose` is being called, which would cause stack
trace warnings.
.. change::
:tags: bug, orm, regression
:tickets: 6793
Fixed critical caching issue where the ORM's persistence feature using
INSERT..RETURNING would cache an incorrect query when mixing the "bulk
save" and standard "flush" forms of INSERT.
.. changelog::
```
### 1.4.21
```
:released: July 14, 2021
.. change::
:tags: usecase, orm
:tickets: 6708
Modified the approach used for history tracking of scalar object
relationships that are not many-to-one, i.e. one-to-one relationships that
would otherwise be one-to-many. When replacing a one-to-one value, the
"old" value that would be replaced is no longer loaded immediately, and is
instead handled during the flush process. This eliminates an historically
troublesome lazy load that otherwise often occurs when assigning to a
one-to-one attribute, and is particularly troublesome when using
"lazy='raise'" as well as asyncio use cases.
This change does cause a behavioral change within the
:meth:`_orm.AttributeEvents.set` event, which is nonetheless currently
documented, which is that the event applied to such a one-to-one attribute
will no longer receive the "old" parameter if it is unloaded and the
:paramref:`_orm.relationship.active_history` flag is not set. As is
documented in :meth:`_orm.AttributeEvents.set`, if the event handler needs
to receive the "old" value when the event fires off, the active_history
flag must be established either with the event listener or with the
relationship. This is already the behavior with other kinds of attributes
such as many-to-one and column value references.
The change additionally will defer updating a backref on the "old" value
in the less common case that the "old" value is locally present in the
session, but isn't loaded on the relationship in question, until the
next flush occurs. If this causes an issue, again the normal
:paramref:`_orm.relationship.active_history` flag can be set to ``True``
on the relationship.
.. change::
:tags: usecase, sql
:tickets: 6752
Added new method :meth:`_sql.HasCTE.add_cte` to each of the
:func:`_sql.select`, :func:`_sql.insert`, :func:`_sql.update` and
:func:`_sql.delete` constructs. This method will add the given
:class:`_sql.CTE` as an "independent" CTE of the statement, meaning it
renders in the WITH clause above the statement unconditionally even if it
is not otherwise referenced in the primary statement. This is a popular use
case on the PostgreSQL database where a CTE is used for a DML statement
that runs against database rows independently of the primary statement.
.. change::
:tags: bug, postgresql
:tickets: 6755
Fixed issue in :meth:`_postgresql.Insert.on_conflict_do_nothing` and
:meth:`_postgresql.Insert.on_conflict_do_update` where the name of a unique
constraint passed as the ``constraint`` parameter would not be properly
truncated for length if it were based on a naming convention that generated
a too-long name for the PostgreSQL max identifier length of 63 characters,
in the same way which occurs within a CREATE TABLE statement.
.. change::
:tags: bug, sql
:tickets: 6710
Fixed issue in CTE constructs where a recursive CTE that referred to a
SELECT that has duplicate column names, which are typically deduplicated
using labeling logic in 1.4, would fail to refer to the deduplicated label
name correctly within the WITH clause.
.. change::
:tags: bug, regression, mssql
:tickets: 6697
Fixed regression where the special dotted-schema name handling for the SQL
Server dialect would not function correctly if the dotted schema name were
used within the ``schema_translate_map`` feature.
.. change::
:tags: orm, regression
:tickets: 6718
Fixed ORM regression where ad-hoc label names generated for hybrid
properties and potentially other similar types of ORM-enabled expressions
would usually be propagated outwards through subqueries, allowing the name
to be retained in the final keys of the result set even when selecting from
subqueries. Additional state is now tracked in this case that isn't lost
when a hybrid is selected out of a Core select / subquery.
.. change::
:tags: bug, postgresql
:tickets: 6739
Fixed issue where the PostgreSQL ``ENUM`` datatype as embedded in the
``ARRAY`` datatype would fail to emit correctly in create/drop when the
``schema_translate_map`` feature were also in use. Additionally repairs a
related issue where the same ``schema_translate_map`` feature would not
work for the ``ENUM`` datatype in combination with a ``CAST``, that's also
intrinsic to how the ``ARRAY(ENUM)`` combination works on the PostgreSQL
dialect.
.. change::
:tags: bug, sql, regression
:tickets: 6735
Fixed regression where the :func:`_sql.tablesample` construct would fail to
be executable when constructed given a floating-point sampling value not
embedded within a SQL function.
.. change::
:tags: bug, postgresql
:tickets: 6696
Fixed issue in :meth:`_postgresql.Insert.on_conflict_do_nothing` and
:meth:`_postgresql.Insert.on_conflict_do_update` where the name of a unique
constraint passed as the ``constraint`` parameter would not be properly
quoted if it contained characters which required quoting.
.. change::
:tags: bug, regression, orm
:tickets: 6698
Fixed regression caused in 1.4.19 due to :ticket:`6503` and related
involving :meth:`_orm.Query.with_entities` where the new structure used
would be inappropriately transferred to an enclosing :class:`_orm.Query`
when making use of set operations such as :meth:`_orm.Query.union`, causing
the JOIN instructions within to be applied to the outside query as well.
.. change::
:tags: bug, orm, regression
:tickets: 6762
Fixed regression which appeared in version 1.4.3 due to :ticket:`6060`
where rules that limit ORM adaptation of derived selectables interfered
with other ORM-adaptation based cases, in this case when applying
adaptations for a :func:`_orm.with_polymorphic` against a mapping which
uses a :func:`_orm.column_property` which in turn makes use of a scalar
select that includes a :func:`_orm.aliased` object of the mapped table.
.. changelog::
```
### 1.4.20
```
:released: June 28, 2021
.. change::
:tags: bug, regression, orm
:tickets: 6680
Fixed regression in ORM regarding an internal reconstitution step for the
:func:`_orm.with_polymorphic` construct, when the user-facing object is
garbage collected as the query is processed. The reconstitution was not
ensuring the sub-entities for the "polymorphic" case were handled, leading
to an ``AttributeError``.
.. change::
:tags: usecase, sql
:tickets: 6646
Add a impl parameter to :class:`_types.PickleType` constructor, allowing
any arbitrary type to be used in place of the default implementation of
:class:`_types.LargeBinary`. Pull request courtesy jason3gb.
.. change::
:tags: bug, engine
:tickets: 5348
Fixed an issue in the C extension for the :class:`_result.Row` class which
could lead to a memory leak in the unlikely case of a :class:`_result.Row`
object which referred to an ORM object that then was mutated to refer back
to the ``Row`` itself, creating a cycle. The Python C APIs for tracking GC
cycles has been added to the native :class:`_result.Row` implementation to
accommodate for this case.
.. change::
:tags: bug, engine
:tickets: 6665
Fixed old issue where a :func:`_sql.select()` made against the token "*",
which then yielded exactly one column, would fail to correctly organize the
``cursor.description`` column name into the keys of the result object.
.. change::
:tags: usecase, mysql
:tickets: 6659
Made a small adjustment in the table reflection feature of the MySQL
dialect to accommodate for alternate MySQL-oriented databases such as TiDB
which include their own "comment" directives at the end of a constraint
directive within "CREATE TABLE" where the format doesn't have the
additional space character after the comment, in this case the TiDB
"clustered index" feature. Pull request courtesy Daniël van Eeden.
.. change::
:tags: bug, schema
:tickets: 6685
Fixed issue where passing ``None`` for the value of
:paramref:`_schema.Table.prefixes` would not store an empty list, but
rather the constant ``None``, which may be unexpected by third party
dialects. The issue is revealed by a usage in recent versions of Alembic
that are passing ``None`` for this value. Pull request courtesy Kai
Mueller.
.. change::
:tags: bug, regression, ext
:tickets: 6679
Fixed regression in :mod:`sqlalchemy.ext.automap` extension such that the
use case of creating an explicit mapped class to a table that is also the
:paramref:`_orm.relationship.secondary` element of a
:func:`_orm.relationship` that automap will be generating would emit the
"overlaps" warnings introduced in 1.4 and discussed at :ref:`error_qzyx`.
While generating this case from automap is still subject to the same
caveats that the "overlaps" warning refers towards, as automap is intended
for more ad-hoc use cases, the condition which produces the warning is
disabled when a many-to-many relationship with this particular pattern is
generated.
.. change::
:tags: bug, regression, orm
:tickets: 6678
Adjusted :meth:`_orm.Query.union` and similar set operations to be
correctly compatible with the new capabilities just added in
:ticket:`6661`, with SQLAlchemy 1.4.19, such that the SELECT statements
rendered as elements of the UNION or other set operation will include
directly mapped columns that are mapped as deferred; this both fixes a
regression involving unions with multiple levels of nesting that would
produce a column mismatch, and also allows the :func:`_orm.undefer` option
to be used at the top level of such a :class:`_orm.Query` without having to
apply the option to each of the elements within the UNION.
.. change::
:tags: bug, sql, orm
:tickets: 6668
Fixed the class hierarchy for the :class:`_schema.Sequence` and the more
general :class:`_schema.DefaultGenerator` base, as these are "executable"
as statements they need to include :class:`_sql.Executable` in their
hierarchy, not just :class:`_roles.StatementRole` as was applied
arbitrarily to :class:`_schema.Sequence` previously. The fix allows
:class:`_schema.Sequence` to work in all ``.execute()`` methods including
with :meth:`_orm.Session.execute` which was not working in the case that a
:meth:`_orm.SessionEvents.do_orm_execute` handler was also established.
.. change::
:tags: bug, orm
:tickets: 6538
Adjusted the check in the mapper for a callable object that is used as a
``validates`` validator function or a ``reconstructor`` reconstruction
function, to check for "callable" more liberally such as to accommodate
objects based on fundamental attributes like ``__func__`` and
``__call___``, rather than testing for ``MethodType`` / ``FunctionType``,
allowing things like cython functions to work properly. Pull request
courtesy Miłosz Stypiński.
.. changelog::
```
### 1.4.19
```
:released: June 22, 2021
.. change::
:tags: bug, mssql
:tickets: 6658
Fixed bug where the "schema_translate_map" feature would fail to function
correctly in conjunction with an INSERT into a table that has an IDENTITY
column, where the value of the IDENTITY column were specified in the values
of the INSERT thus triggering SQLAlchemy's feature of setting IDENTITY
INSERT to "on"; it's in this directive where the schema translate map would
fail to be honored.
.. change::
:tags: bug, sql
:tickets: 6663
Fixed issue in CTE constructs mostly relevant to ORM use cases where a
recursive CTE against "anonymous" labels such as those seen in ORM
``column_property()`` mappings would render in the
``WITH RECURSIVE xyz(...)`` section as their raw internal label and not a
cleanly anonymized name.
.. change::
:tags: mssql, change
:tickets: 6503, 6253
Made improvements to the server version regexp used by the pymssql dialect
to prevent a regexp overflow in case of an invalid version string.
.. change::
:tags: bug, orm, regression
:tickets: 6503, 6253
Fixed further regressions in the same area as that of :ticket:`6052` where
loader options as well as invocations of methods like
:meth:`_orm.Query.join` would fail if the left side of the statement for
which the option/join depends upon were replaced by using the
:meth:`_orm.Query.with_entities` method, or when using 2.0 style queries
when using the :meth:`_sql.Select.with_only_columns` method. A new set of
state has been added to the objects which tracks the "left" entities that
the options / join were made against which is memoized when the lead
entities are changed.
.. change::
:tags: bug, asyncio, postgresql
:tickets: 6652
Fixed bug in asyncio implementation where the greenlet adaptation system
failed to propagate ``BaseException`` subclasses, most notably including
``asyncio.CancelledError``, to the exception handling logic used by the
engine to invalidate and clean up the connection, thus preventing
connections from being correctly disposed when a task was cancelled.
.. change::
:tags: usecase, asyncio
:tickets: 6583
Implemented :class:`_asyncio.async_scoped_session` to address some
asyncio-related incompatibilities between :class:`_orm.scoped_session` and
:class:`_asyncio.AsyncSession`, in which some methods (notably the
:meth:`_asyncio.async_scoped_session.remove` method) should be used with
the ``await`` keyword.
.. seealso::
:ref:`asyncio_scoped_session`
.. change::
:tags: usecase, mysql
:tickets: 6132
Added new construct :class:`_mysql.match`, which provides for the full
range of MySQL's MATCH operator including multiple column support and
modifiers. Pull request courtesy Anton Kovalevich.
.. seealso::
:class:`_mysql.match`
.. change::
:tags: bug, postgresql, oracle
:tickets: 6649
Fixed issue where the ``INTERVAL`` datatype on PostgreSQL and Oracle would
produce an ``AttributeError`` when used in the context of a comparison
operation against a ``timedelta()`` object. Pull request courtesy
MajorDallas.
.. change::
:tags: bug, mypy
:tickets: 6476
Fixed issue in mypy plugin where class info for a custom declarative base
would not be handled correctly on a cached mypy pass, leading to an
AssertionError being raised.
.. change::
:tags: bug, orm
:tickets: 6661
Refined the behavior of ORM subquery rendering with regards to deferred
columns and column properties to be more compatible with that of 1.3 while
also providing for 1.4's newer features. As a subquery in 1.4 does not make
use of loader options, including :func:`_orm.undefer`, a subquery that is
against an ORM entity with deferred attributes will now render those
deferred attributes that refer directly to mapped table columns, as these
are needed in the outer SELECT if that outer SELECT makes use of these
columns; however a deferred attribute that refers to a composed SQL
expression as we normally do with :func:`_orm.column_property` will not be
part of the subquery, as these can be selected explicitly if needed in the
subquery. If the entity is being SELECTed from this subquery, the column
expression can still render on "the outside" in terms of the derived
subquery columns. This produces essentially the same behavior as when
working with 1.3. However in this case the fix has to also make sure that
the ``.selected_columns`` collection of an ORM-enabled :func:`_sql.select`
also follows these rules, which in particular allows recursive CTEs to
render correctly in this scenario, which were previously failing to render
correctly due to this issue.
.. change::
:tags: bug, postgresql
:tickets: 6621
Fixed issue where the pool "pre ping" feature would implicitly start a
transaction, which would then interfere with custom transactional flags
such as PostgreSQL's "read only" mode when used with the psycopg2 driver.
.. changelog::
```
### 1.4.18
```
:released: June 10, 2021
.. change::
:tags: bug, orm
:tickets: 6072, 6487
Clarified the current purpose of the
:paramref:`_orm.relationship.bake_queries` flag, which in 1.4 is to enable
or disable "lambda caching" of statements within the "lazyload" and
"selectinload" loader strategies; this is separate from the more
foundational SQL query cache that is used for most statements.
Additionally, the lazy loader no longer uses its own cache for many-to-one
SQL queries, which was an implementation quirk that doesn't exist for any
other loader scenario. Finally, the "lru cache" warning that the lazyloader
and selectinloader strategies could emit when handling a wide array of
class/relationship combinations has been removed; based on analysis of some
end-user cases, this warning doesn't suggest any significant issue. While
setting ``bake_queries=False`` for such a relationship will remove this
cache from being used, there's no particular performance gain in this case
as using no caching vs. using a cache that needs to refresh often likely
still wins out on the caching being used side.
.. change::
:tags: bug, asyncio
:tickets: 6575
Fixed an issue that presented itself when using the :class:`_pool.NullPool`
or the :class:`_pool.StaticPool` with an async engine. This mostly affected
the aiosqlite dialect.
.. change::
:tags: bug, sqlite, regression
:tickets: 6586
The fix for pysqlcipher released in version 1.4.3 :ticket:`5848` was
unfortunately non-working, in that the new ``on_connect_url`` hook was
erroneously not receiving a ``URL`` object under normal usage of
:func:`_sa.create_engine` and instead received a string that was unhandled;
the test suite failed to fully set up the actual conditions under which
this hook is called. This has been fixed.
.. change::
:tags: bug, postgresql, regression
:tickets: 6581
Fixed regression where using the PostgreSQL "INSERT..ON CONFLICT" structure
would fail to work with the psycopg2 driver if it were used in an
"executemany" context along with bound parameters in the "SET" clause, due
to the implicit use of the psycopg2 fast execution helpers which are not
appropriate for this style of INSERT statement; as these helpers are the
default in 1.4 this is effectively a regression. Additional checks to
exclude this kind of statement from that particular extension have been
added.
.. change::
:tags: bug, orm, regression
:tickets: 6285
Adjusted the means by which classes such as :class:`_orm.scoped_session`
and :class:`_asyncio.AsyncSession` are generated from the base
:class:`_orm.Session` class, such that custom :class:`_orm.Session`
subclasses such as that used by Flask-SQLAlchemy don't need to implement
positional arguments when they call into the superclass method, and can
continue using the same argument styles as in previous releases.
.. change::
:tags: bug, orm, regression
:tickets: 6595
Fixed issue where query production for joinedload against a complex left
hand side involving joined-table inheritance could fail to produce a
correct query, due to a clause adaption issue.
.. change::
:tags: bug, orm, regression, performance
:tickets: 6596
Fixed regression involving how the ORM would resolve a given mapped column
to a result row, where under cases such as joined eager loading, a slightly
more expensive "fallback" could take place to set up this resolution due to
some logic that was removed since 1.3. The issue could also cause
deprecation warnings involving column resolution to be emitted when using a
1.4 style query with joined eager loading.
.. change::
:tags: bug, orm
:tickets: 6591
Fixed issue in experimental "select ORM objects from INSERT/UPDATE" use
case where an error was raised if the statement were against a
single-table-inheritance subclass.
.. change::
:tags: bug, asyncio
:tickets: 6592
Added ``asyncio.exceptions.TimeoutError``,
``asyncio.exceptions.CancelledError`` as so-called "exit exceptions", a
class of exceptions that include things like ``GreenletExit`` and
``KeyboardInterrupt``, which are considered to be events that warrant
considering a DBAPI connection to be in an unusable state where it should
be recycled.
.. change::
:tags: bug, orm
:tickets: 6400
The warning that's emitted for :func:`_orm.relationship` when multiple
relationships would overlap with each other as far as foreign key
attributes written towards, now includes the specific "overlaps" argument
to use for each warning in order to silence the warning without changing
the mapping.
.. change::
:tags: usecase, asyncio
:tickets: 6319
Implemented a new regist
pyup-bot
commented
2 years ago
This PR updates SQLAlchemy from 1.2.12 to 1.4.35.
Changelog
### 1.4.27 ``` :include_notes_from: unreleased_14 .. changelog:: ``` ### 1.4.26 ``` :released: October 19, 2021 .. change:: :tags: orm :tickets: 6284 Passing a :class:`.Query` object to :meth:`_orm.Session.execute` is not the intended use of this object, and will now raise a deprecation warning. .. change:: :tags: bug, postgresql :tickets: 5387 Added a "disconnect" condition for the "SSL SYSCALL error: Bad address" error message as reported by psycopg2. Pull request courtesy Zeke Brechtel. .. change:: :tags: bug, orm Improved the exception message generated when configuring a mapping with joined table inheritance where the two tables either have no foreign key relationships set up, or where they have multiple foreign key relationships set up. The message is now ORM specific and includes context that the :paramref:`_orm.Mapper.inherit_condition` parameter may be needed particularly for the ambiguous foreign keys case. .. change:: :tags: bug, sql :tickets: 6520 Fixed issue where SQL queries using the :meth:`_functions.FunctionElement.within_group` construct could not be pickled, typically when using the ``sqlalchemy.ext.serializer`` extension but also for general generic pickling. .. change:: :tags: bug, orm :tickets: 7189 Fixed issue with :func:`_orm.with_loader_criteria` feature where ON criteria would not be added to a JOIN for a query of the form ``select(A).join(B)``, stating a target while making use of an implicit ON clause. .. change:: :tags: bug, orm :tickets: 7205 Fixed bug where the ORM "plugin", necessary for features such as :func:`_orm.with_loader_criteria` to work correctly, would not be applied to a :func:`_sql.select` which queried from an ORM column expression if it made use of the :meth:`_sql.ColumnElement.label` modifier. .. change:: :tags: bug, mypy :tickets: 6435 Fixed issue in mypy plugin to improve upon some issues detecting ``Enum()`` SQL types containing custom Python enumeration classes. Pull request courtesy Hiroshi Ogawa. .. change:: :tags: bug, mysql :tickets: 7144 Fixed issue in MySQL :func:`_mysql.match` construct where passing a clause expression such as :func:`_sql.bindparam` or other SQL expression for the "against" parameter would fail. Pull request courtesy Anton Kovalevich. .. change:: :tags: bug, mssql :tickets: 7160 Fixed issue with :meth:`.Inspector.get_foreign_keys` where foreign keys were omitted if they were established against a unique index instead of a unique constraint. .. change:: :tags: usecase, mssql Added reflection support for SQL Server foreign key options, including "ON UPDATE" and "ON DELETE" values of "CASCADE" and "SET NULL". .. change:: :tags: bug, sql :tickets: 4123 Repaired issue in new :paramref:`_sql.HasCTE.cte.nesting` parameter introduced with :ticket:`4123` where a recursive :class:`_sql.CTE` using :paramref:`_sql.HasCTE.cte.recursive` in typical conjunction with UNION would not compile correctly. Additionally makes some adjustments so that the :class:`_sql.CTE` construct creates a correct cache key. Pull request courtesy Eric Masseran. .. change:: :tags: bug, engine :tickets: 7130 Fixed issue where the deprecation warning for the :class:`.URL` constructor which indicates that the :meth:`.URL.create` method should be used would not emit if a full positional argument list of seven arguments were passed; additionally, validation of URL arguments will now occur if the constructor is called in this way, which was being skipped previously. .. change:: :tags: bug, orm :tickets: 7103 Add missing methods added in :ticket:`6991` to :class:`_scoping.scoped_session` and :func:`_asyncio.async_scoped_session`. .. change:: :tags: bug, examples :tickets: 7169 Repaired the examples in examples/versioned_rows to use SQLAlchemy 1.4 APIs correctly; these examples had been missed when API changes like removing "passive" from :meth:`_orm.Session.is_modified` were made as well as the :meth:`_ormevents.SessionEvents.do_orm_execute()` event hook were added. .. change:: :tags: bug, orm :tickets: 6974, 6972 An extra layer of warning messages has been added to the functionality of :meth:`_orm.Query.join` and the ORM version of :meth:`_sql.Select.join`, where a few places where "automatic aliasing" continues to occur will now be called out as a pattern to avoid, mostly specific to the area of joined table inheritance where classes that share common base tables are being joined together without using explicit aliases. One case emits a legacy warning for a pattern that's not recommended, the other case is fully deprecated. The automatic aliasing within ORM join() which occurs for overlapping mapped tables does not work consistently with all APIs such as :func:`_orm.contains_eager()`, and rather than continue to try to make these use cases work everywhere, replacing with a more user-explicit pattern is clearer, less prone to bugs and simplifies SQLAlchemy's internals further. The warnings include links to the errors.rst page where each pattern is demonstrated along with the recommended pattern to fix. .. seealso:: :ref:`error_xaj1` :ref:`error_xaj2` .. change:: :tags: bug, sql :tickets: 7061 Account for the :paramref:`_sql.table.schema` parameter passed to the :func:`_sql.table` construct, such that it is taken into account when accessing the :attr:`_sql.TableClause.fullname` attribute. .. change:: :tags: bug, sql :tickets: 7140 Fixed an inconsistency in the :meth:`_sql.ColumnOperators.any_` / :meth:`_sql.ColumnOperators.all_` functions / methods where the special behavior these functions have of "flipping" the expression such that the "ANY" / "ALL" expression is always on the right side would not function if the comparison were against the None value, that is, "column.any_() == None" should produce the same SQL expression as "null() == column.any_()". Added more docs to clarify this as well, plus mentions that any_() / all_() generally supersede the ARRAY version "any()" / "all()". .. change:: :tags: engine, bug, postgresql :tickets: 3247 The :meth:`_reflection.Inspector.reflect_table` method now supports reflecting tables that do not have user defined columns. This allows :meth:`_schema.MetaData.reflect` to properly complete reflection on databases that contain such tables. Currently, only PostgreSQL is known to support such a construct among the common database backends. .. change:: :tags: sql, bug, regression :tickets: 7177 Fixed issue where "expanding IN" would fail to function correctly with datatypes that use the :meth:`_types.TypeEngine.bind_expression` method, where the method would need to be applied to each element of the IN expression rather than the overall IN expression itself. .. change:: :tags: postgresql, bug, regression :tickets: 7177 Fixed issue where IN expressions against a series of array elements, as can be done with PostgreSQL, would fail to function correctly due to multiple issues within the "expanding IN" feature of SQLAlchemy Core that was standardized in version 1.4. The psycopg2 dialect now makes use of the :meth:`_types.TypeEngine.bind_expression` method with :class:`_types.ARRAY` to portably apply the correct casts to elements. The asyncpg dialect was not affected by this issue as it applies bind-level casts at the driver level rather than at the compiler level. .. change:: :tags: bug, mysql :tickets: 7204 Fixed installation issue where the ``sqlalchemy.dialects.mysql`` module would not be importable if "greenlet" were not installed. .. change:: :tags: bug, mssql :tickets: 7168 Fixed issue with :meth:`.Inspector.has_table` where it would return False if a local temp table with the same name from a different session happened to be returned first when querying tempdb. This is a continuation of :ticket:`6910` which accounted for the temp table existing only in the alternate session and not the current one. .. change:: :tags: bug, orm :tickets: 7128 Fixed bug where iterating a :class:`.Result` from a :class:`_orm.Session` after that :class:`_orm.Session` were closed would partially attach objects to that session in an essentially invalid state. It now raises an exception with a link to new documentation if an **un-buffered** result is iterated from a :class:`_orm.Session` that was closed or otherwise had the :meth:`_orm.Session.expunge_all` method called after that :class:`.Result` was generated. The ``prebuffer_rows`` execution option, as is used automatically by the asyncio extension for client-side result sets, may be used to produce a :class:`.Result` where the ORM objects are prebuffered, and in this case iterating the result will produce a series of detached objects. .. seealso:: :ref:`error_lkrp` .. change:: :tags: bug, mssql, regression :tickets: 7129 Fixed bug in SQL Server :class:`_mssql.DATETIMEOFFSET` datatype where the ODBC implementation would not generate the correct DDL, for cases where the type were converted using the ``dialect.type_descriptor()`` method, the usage of which is illustrated in some documented examples for :class:`.TypeDecorator`, though not necessary for most datatypes. Regression was introduced by :ticket:`6366`. As part of this change, the full list of SQL Server date types have been amended to return a "dialect impl" that generates the same DDL name as the supertype. .. change:: :tags: bug, sql :tickets: 7153 Adjusted the "column disambiguation" logic that's new in 1.4, where the same expression repeated gets an "extra anonymous" label, so that the logic more aggressively deduplicates those labels when the repeated element is the same Python expression object each time, as occurs in cases like when using "singleton" values like :func:`_sql.null`. This is based on the observation that at least some databases (e.g. MySQL, but not SQLite) will raise an error if the same label is repeated inside of a subquery. .. change:: :tags: bug, orm :tickets: 7154 Related to :ticket:`7153`, fixed an issue where result column lookups would fail for "adapted" SELECT statements that selected for "constant" value expressions most typically the NULL expression, as would occur in such places as joined eager loading in conjunction with limit/offset. This was overall a regression due to issue :ticket:`6259` which removed all "adaption" for constants like NULL, "true", and "false" when rewriting expressions in a SQL statement, but this broke the case where the same adaption logic were used to resolve the constant to a labeled expression for the purposes of result set targeting. .. change:: :tags: bug, orm, regression :tickets: 7134 Fixed regression where ORM loaded objects could not be pickled in cases where loader options making use of ``"*"`` were used in certain combinations, such as combining the :func:`_orm.joinedload` loader strategy with ``raiseload('*')`` of sub-elements. .. change:: :tags: bug, engine :tickets: 7077 Implemented proper ``__reduce__()`` methods for all SQLAlchemy exception objects to ensure they all support clean round trips when pickling, as exception objects are often serialized for the purposes of various debugging tools. .. change:: :tags: bug, orm, regression :tickets: 7209 Fixed regression where the use of a :class:`_hybrid.hybrid_property` attribute or a mapped :func:`_orm.composite` attribute as a key passed to the :meth:`_dml.Update.values` method for an ORM-enabled :class:`_dml.Update` statement, as well as when using it via the legacy :meth:`_orm.Query.update` method, would be processed for incoming ORM/hybrid/composite values within the compilation stage of the UPDATE statement, which meant that in those cases where caching occurred, subsequent invocations of the same statement would no longer receive the correct values. This would include not only hybrids that use the :meth:`_hybrid.hybrid_property.update_expression` method, but any use of a plain hybrid attribute as well. For composites, the issue instead caused a non-repeatable cache key to be generated, which would break caching and could fill up the statement cache with repeated statements. The :class:`_dml.Update` construct now handles the processing of key/value pairs passed to :meth:`_dml.Update.values` and :meth:`_dml.Update.ordered_values` up front when the construct is first generated, before the cache key has been generated so that the key/value pairs are processed each time, and so that the cache key is generated against the individual column/value pairs that will ultimately be used in the statement. .. changelog:: ``` ### 1.4.25 ``` :released: September 22, 2021 .. change:: :tags: bug, platform, regression :tickets: 7024 Fixed regression due to :ticket:`7024` where the reorganization of the "platform machine" names used by the ``greenlet`` dependency mis-spelled "aarch64" and additionally omitted uppercase "AMD64" as is needed for Windows machines. Pull request courtesy James Dow. .. changelog:: ``` ### 1.4.24 ``` :released: September 22, 2021 .. change:: :tags: bug, asyncio :tickets: 6943 Fixed a bug in :meth:`_asyncio.AsyncSession.execute` and :meth:`_asyncio.AsyncSession.stream` that required ``execution_options`` to be an instance of ``immutabledict`` when defined. It now correctly accepts any mapping. .. change:: :tags: engine, asyncio, usecase :tickets: 6832 Improve the interface used by adapted drivers, like the asyncio ones, to access the actual connection object returned by the driver. The :class:`._ConnectionFairy` object has two new attributes: * :attr:`._ConnectionFairy.dbapi_connection` always represents a DBAPI compatible object. For pep-249 drivers, this is the DBAPI connection as it always has been, previously accessed under the ``.connection`` attribute. For asyncio drivers that SQLAlchemy adapts into a pep-249 interface, the returned object will normally be a SQLAlchemy adaption object called :class:`_engine.AdaptedConnection`. * :attr:`._ConnectionFairy.driver_connection` always represents the actual connection object maintained by the third party pep-249 DBAPI or async driver in use. For standard pep-249 DBAPIs, this will always be the same object as that of the ``dbapi_connection``. For an asyncio driver, it will be the underlying asyncio-only connection object. The ``.connection`` attribute remains available and is now a legacy alias of ``.dbapi_connection``. .. seealso:: :ref:`faq_dbapi_connection` .. change:: :tags: bug, sql :tickets: 7052 Implemented missing methods in :class:`_functions.FunctionElement` which, while unused, would lead pylint to report them as unimplemented abstract methods. .. change:: :tags: bug, mssql, reflection :tickets: 6910 Fixed an issue where :meth:`_reflection.has_table` returned ``True`` for local temporary tables that actually belonged to a different SQL Server session (connection). An extra check is now performed to ensure that the temp table detected is in fact owned by the current session. .. change:: :tags: bug, engine, regression :tickets: 6913 Fixed issue where the ability of the :meth:`_events.ConnectionEvents.before_execute` method to alter the SQL statement object passed, returning the new object to be invoked, was inadvertently removed. This behavior has been restored. .. change:: :tags: bug, engine :tickets: 6958 Ensure that ``str()`` is called on the an :paramref:`_url.URL.create.password` argument, allowing usage of objects that implement the ``__str__()`` method as password attributes. Also clarified that one such object is not appropriate to dynamically change the password for each database connection; the approaches at :ref:`engines_dynamic_tokens` should be used instead. .. change:: :tags: bug, orm, regression :tickets: 6979 Fixed ORM issue where column expressions passed to ``query()`` or ORM-enabled ``select()`` would be deduplicated on the identity of the object, such as a phrase like ``select(A.id, null(), null())`` would produce only one "NULL" expression, which previously was not the case in 1.3. However, the change also allows for ORM expressions to render as given as well, such as ``select(A.data, A.data)`` will produce a result row with two columns. .. change:: :tags: bug, engine :tickets: 6983 Fixed issue in :class:`_engine.URL` where validation of "drivername" would not appropriately respond to the ``None`` value where a string were expected. .. change:: :tags: bug, mypy :tickets: 6950 Fixed issue where mypy plugin would crash when interpreting a ``query_expression()`` construct. .. change:: :tags: usecase, sql :tickets: 4123 Added new parameter :paramref:`_sql.HasCTE.cte.nesting` to the :class:`_sql.CTE` constructor and :meth:`_sql.HasCTE.cte` method, which flags the CTE as one which should remain nested within an enclosing CTE, rather than being moved to the top level of the outermost SELECT. While in the vast majority of cases there is no difference in SQL functionality, users have identified various edge-cases where true nesting of CTE constructs is desirable. Much thanks to Eric Masseran for lots of work on this intricate feature. .. change:: :tags: usecase, engine, orm :tickets: 6990 Added new methods :meth:`_orm.Session.scalars`, :meth:`_engine.Connection.scalars`, :meth:`_asyncio.AsyncSession.scalars` and :meth:`_asyncio.AsyncSession.stream_scalars`, which provide a short cut to the use case of receiving a row-oriented :class:`_result.Result` object and converting it to a :class:`_result.ScalarResult` object via the :meth:`_engine.Result.scalars` method, to return a list of values rather than a list of rows. The new methods are analogous to the long existing :meth:`_orm.Session.scalar` and :meth:`_engine.Connection.scalar` methods used to return a single value from the first row only. Pull request courtesy Miguel Grinberg. .. change:: :tags: usecase, orm :tickets: 6955 Added loader options to :meth:`_orm.Session.merge` and :meth:`_asyncio.AsyncSession.merge` via a new :paramref:`_orm.Session.merge.options` parameter, which will apply the given loader options to the ``get()`` used internally by merge, allowing eager loading of relationships etc. to be applied when the merge process loads a new object. Pull request courtesy Daniel Stone. .. change:: :tags: feature, asyncio, mysql :tickets: 6993 Added initial support for the ``asyncmy`` asyncio database driver for MySQL and MariaDB. This driver is very new, however appears to be the only current alternative to the ``aiomysql`` driver which currently appears to be unmaintained and is not working with current Python versions. Much thanks to long2ice for the pull request for this dialect. .. seealso:: :ref:`asyncmy` .. change:: :tags: bug, asyncio Added missing ``**kw`` arguments to the :meth:`_asyncio.AsyncSession.connection` method. .. change:: :tags: bug, sql :tickets: 7055 Fixed a two issues where combinations of ``select()`` and ``join()`` when adapted to form a copy of the element would not completely copy the state of all column objects associated with subqueries. A key problem this caused is that usage of the :meth:`_sql.ClauseElement.params` method (which should probably be moved into a legacy category as it is inefficient and error prone) would leave copies of the old :class:`_sql.BindParameter` objects around, leading to issues in correctly setting the parameters at execution time. .. change:: :tags: bug, orm, regression :tickets: 6924 Fixed issue in recently repaired ``Query.with_entities()`` method where the flag that determines automatic uniquing for legacy ORM ``Query`` objects only would be set to ``True`` inappropriately in cases where the ``with_entities()`` call would be setting the ``Query`` to return column-only rows, which are not uniqued. .. change:: :tags: bug, postgresql :tickets: 6912 Qualify ``version()`` call to avoid shadowing issues if a different search path is configured by the user. .. change:: :tags: bug, engine, postgresql :tickets: 6963 Fixed issue where an engine that had :paramref:`_sa.create_engine.implicit_returning` set to False would fail to function when PostgreSQL's "fast insertmany" feature were used in conjunction with a ``Sequence``, as well as if any kind of "executemany" with "return_defaults()" were used in conjunction with a ``Sequence``. Note that PostgreSQL "fast insertmany" uses "RETURNING" by definition, when the SQL statement is passed to the driver; overall, the :paramref:`_sa.create_engine.implicit_returning` flag is legacy and has no real use in modern SQLAlchemy, and will be deprecated in a separate change. .. change:: :tags: bug, mypy :tickets: 6937 Fixed issue in mypy plugin where columns on a mixin would not be correctly interpreted if the mapped class relied upon a ``__tablename__`` routine that came from a superclass. .. change:: :tags: bug, postgresql :tickets: 6106 The :class:`_postgresql.ENUM` datatype is PostgreSQL-native and therefore should not be used with the ``native_enum=False`` flag. This flag is now ignored if passed to the :class:`_postgresql.ENUM` datatype and a warning is emitted; previously the flag would cause the type object to fail to function correctly. .. change:: :tags: bug, sql :tickets: 7036 Fixed issue related to new :meth:`_sql.HasCTE.add_cte` feature where pairing two "INSERT..FROM SELECT" statements simultaneously would lose track of the two independent SELECT statements, leading to the wrong SQL. .. change:: :tags: asyncio, bug :tickets: 6746 Deprecate usage of :class:`_orm.scoped_session` with asyncio drivers. When using Asyncio the :class:`_asyncio.async_scoped_session` should be used instead. .. change:: :tags: bug, platform :tickets: 7024 Further adjusted the "greenlet" package specifier in setup.cfg to use a long chain of "or" expressions, so that the comparison of ``platform_machine`` to a specific identifier matches only the complete string. .. change:: :tags: bug, sqlite Fixed bug where the error message for SQLite invalid isolation level on the pysqlite driver would fail to indicate that "AUTOCOMMIT" is one of the valid isolation levels. .. change:: :tags: bug, sql :tickets: 7060 Fixed issue where using ORM column expressions as keys in the list of dictionaries passed to :meth:`_sql.Insert.values` for "multi-valued insert" would not be processed correctly into the correct column expressions. .. change:: :tags: asyncio, usecase :tickets: 6746 The :class:`_asyncio.AsyncSession` now supports overriding which :class:`_orm.Session` it uses as the proxied instance. A custom ``Session`` class can be passed using the :paramref:`.AsyncSession.sync_session_class` parameter or by subclassing the ``AsyncSession`` and specifying a custom :attr:`.AsyncSession.sync_session_class`. .. change:: :tags: bug, oracle, performance :tickets: 4486 Added a CAST(VARCHAR2(128)) to the "table name", "owner", and other DDL-name parameters as used in reflection queries against Oracle system views such as ALL_TABLES, ALL_TAB_CONSTRAINTS, etc to better enable indexing to take place against these columns, as they previously would be implicitly handled as NVARCHAR2 due to Python's use of Unicode for strings; these columns are documented in all Oracle versions as being VARCHAR2 with lengths varying from 30 to 128 characters depending on server version. Additionally, test support has been enabled for Unicode-named DDL structures against Oracle databases. .. changelog:: ``` ### 1.4.23 ``` :released: August 18, 2021 .. change:: :tags: bug, sql :tickets: 6752 Fix issue in :class:`_sql.CTE` where new :meth:`_sql.HasCTE.add_cte` method added in version 1.4.21 / :ticket:`6752` failed to function correctly for "compound select" structures such as :func:`_sql.union`, :func:`_sql.union_all`, :func:`_sql.except`, etc. Pull request courtesy Eric Masseran. .. change:: :tags: orm, usecase :tickets: 6808 Added new attribute :attr:`_sql.Select.columns_clause_froms` that will retrieve the FROM list implied by the columns clause of the :class:`_sql.Select` statement. This differs from the old :attr:`_sql.Select.froms` collection in that it does not perform any ORM compilation steps, which necessarily deannotate the FROM elements and do things like compute joinedloads etc., which makes it not an appropriate candidate for the :meth:`_sql.Select.select_from` method. Additionally adds a new parameter :paramref:`_sql.Select.with_only_columns.maintain_column_froms` that transfers this collection to :meth:`_sql.Select.select_from` before replacing the columns collection. In addition, the :attr:`_sql.Select.froms` is renamed to :meth:`_sql.Select.get_final_froms`, to stress that this collection is not a simple accessor and is instead calculated given the full state of the object, which can be an expensive call when used in an ORM context. Additionally fixes a regression involving the :func:`_orm.with_only_columns` function to support applying criteria to column elements that were replaced with either :meth:`_sql.Select.with_only_columns` or :meth:`_orm.Query.with_entities` , which had broken as part of :ticket:`6503` released in 1.4.19. .. change:: :tags: bug, orm, sql :tickets: 6824 Fixed issue where a bound parameter object that was "cloned" would cause a name conflict in the compiler, if more than one clone of this parameter were used at the same time in a single statement. This could occur in particular with things like ORM single table inheritance queries that indicated the same "discriminator" value multiple times in one query. .. change:: :tags: bug, mssql, sql :tickets: 6863 Fixed issue where the ``literal_binds`` compiler flag, as used externally to render bound parameters inline, would fail to work when used with a certain class of parameters known as "literal_execute", which covers things like LIMIT and OFFSET values for dialects where the drivers don't allow a bound parameter, such as SQL Server's "TOP" clause. The issue locally seemed to affect only the MSSQL dialect. .. change:: :tags: bug, orm :tickets: 6869 Fixed issue in loader strategies where the use of the :meth:`_orm.Load.options` method, particularly when nesting multiple calls, would generate an overly long and more importantly non-deterministic cache key, leading to very large cache keys which were also not allowing efficient cache usage, both in terms of total memory used as well as number of entries used in the cache itself. .. change:: :tags: bug, sql :tickets: 6858 Fixed an issue in the ``CacheKey.to_offline_string()`` method used by the dogpile.caching example where attempting to create a proper cache key from the special "lambda" query generated by the lazy loader would fail to include the parameter values, leading to an incorrect cache key. .. change:: :tags: bug, orm :tickets: 6887 Revised the means by which the :attr:`_orm.ORMExecuteState.user_defined_options` accessor receives :class:`_orm.UserDefinedOption` and related option objects from the context, with particular emphasis on the "selectinload" on the loader strategy where this previously was not working; other strategies did not have this problem. The objects that are associated with the current query being executed, and not that of a query being cached, are now propagated unconditionally. This essentially separates them out from the "loader strategy" options which are explicitly associated with the compiled state of a query and need to be used in relation to the cached query. The effect of this fix is that a user-defined option, such as those used by the dogpile.caching example as well as for other recipes such as defining a "shard id" for the horizontal sharing extension, will be correctly propagated to eager and lazy loaders regardless of whether a cached query was ultimately invoked. .. change:: :tags: bug, sql :tickets: 6886 Adjusted the "from linter" warning feature to accommodate for a chain of joins more than one level deep where the ON clauses don't explicitly match up the targets, such as an expression such as "ON TRUE". This mode of use is intended to cancel the cartesian product warning simply by the fact that there's a JOIN from "a to b", which was not working for the case where the chain of joins had more than one element. .. change:: :tags: bug, postgresql :tickets: 6886 Added the "is_comparison" flag to the PostgreSQL "overlaps", "contained_by", "contains" operators, so that they work in relevant ORM contexts as well as in conjunction with the "from linter" feature. .. change:: :tags: bug, orm :tickets: 6812 Fixed issue where the unit of work would internally use a 2.0-deprecated SQL expression form, emitting a deprecation warning when SQLALCHEMY_WARN_20 were enabled. .. change:: :tags: bug, orm :tickets: 6881 Fixed issue in :func:`_orm.selectinload` where use of the new :meth:`_orm.PropComparator.and_` feature within options that were nested more than one level deep would fail to update bound parameter values that were in the nested criteria, as a side effect of SQL statement caching. .. change:: :tags: bug, general :tickets: 6136 The setup requirements have been modified such ``greenlet`` is a default requirement only for those platforms that are well known for ``greenlet`` to be installable and for which there is already a pre-built binary on pypi; the current list is ``x86_64 aarch64 ppc64le amd64 win32``. For other platforms, greenlet will not install by default, which should enable installation and test suite running of SQLAlchemy 1.4 on platforms that don't support ``greenlet``, excluding any asyncio features. In order to install with the ``greenlet`` dependency included on a machine architecture outside of the above list, the ``[asyncio]`` extra may be included by running ``pip install sqlalchemy[asyncio]`` which will then attempt to install ``greenlet``. Additionally, the test suite has been repaired so that tests can complete fully when greenlet is not installed, with appropriate skips for asyncio-related tests. .. change:: :tags: enum, schema :tickets: 6146 Unify behaviour :class:`_schema.Enum` in native and non-native implementations regarding the accepted values for an enum with aliased elements. When :paramref:`_schema.Enum.omit_aliases` is ``False`` all values, alias included, are accepted as valid values. When :paramref:`_schema.Enum.omit_aliases` is ``True`` only non aliased values are accepted as valid values. .. change:: :tags: bug, ext :tickets: 6816 Fixed issue where the horizontal sharding extension would not correctly accommodate for a plain textual SQL statement passed to :meth:`_orm.Session.execute`. .. change:: :tags: bug, orm :tickets: 6889, 6079 Adjusted ORM loader internals to no longer use the "lambda caching" system that was added in 1.4, as well as repaired one location that was still using the previous "baked query" system for a query. The lambda caching system remains an effective way to reduce the overhead of building up queries that have relatively fixed usage patterns. In the case of loader strategies, the queries used are responsible for moving through lots of arbitrary options and criteria, which is both generated and sometimes consumed by end-user code, that make the lambda cache concept not any more efficient than not using it, at the cost of more complexity. In particular the problems noted by :ticket:`6881` and :ticket:`6887` are made are made considerably less complicated by removing this feature internally. .. change:: :tags: bug, orm :tickets: 6889 Fixed an issue where the :class:`_orm.Bundle` construct would not create proper cache keys, leading to inefficient use of the query cache. This had some impact on the "selectinload" strategy and was identified as part of :ticket:`6889`. .. change:: :tags: usecase, mypy :tickets: 6804, 6759 Added support for SQLAlchemy classes to be defined in user code using "generic class" syntax as defined by ``sqlalchemy2-stubs``, e.g. ``Column[String]``, without the need for qualifying these constructs within a ``TYPE_CHECKING`` block by implementing the Python special method ``__class_getitem__()``, which allows this syntax to pass without error at runtime. .. change:: :tags: bug, sql Fixed issue in lambda caching system where an element of a query that produces no cache key, like a custom option or clause element, would still populate the expression in the "lambda cache" inappropriately. .. changelog:: ``` ### 1.4.22 ``` :released: July 21, 2021 .. change:: :tags: bug, sql :tickets: 6786 Fixed issue where use of the :paramref:`_sql.case.whens` parameter passing a dictionary positionally and not as a keyword argument would emit a 2.0 deprecation warning, referring to the deprecation of passing a list positionally. The dictionary format of "whens", passed positionally, is still supported and was accidentally marked as deprecated. .. change:: :tags: bug, orm :tickets: 6775 Fixed issue in new :meth:`_schema.Table.table_valued` method where the resulting :class:`_sql.TableValuedColumn` construct would not respond correctly to alias adaptation as is used throughout the ORM, such as for eager loading, polymorphic loading, etc. .. change:: :tags: bug, orm :tickets: 6769 Fixed issue where usage of the :meth:`_result.Result.unique` method with an ORM result that included column expressions with unhashable types, such as ``JSON`` or ``ARRAY`` using non-tuples would silently fall back to using the ``id()`` function, rather than raising an error. This now raises an error when the :meth:`_result.Result.unique` method is used in a 2.0 style ORM query. Additionally, hashability is assumed to be True for result values of unknown type, such as often happens when using SQL functions of unknown return type; if values are truly not hashable then the ``hash()`` itself will raise. For legacy ORM queries, since the legacy :class:`_orm.Query` object uniquifies in all cases, the old rules remain in place, which is to use ``id()`` for result values of unknown type as this legacy uniquing is mostly for the purpose of uniquing ORM entities and not column values. .. change:: :tags: orm, bug :tickets: 6771 Fixed an issue where clearing of mappers during things like test suite teardowns could cause a "dictionary changed size" warning during garbage collection, due to iteration of a weak-referencing dictionary. A ``list()`` has been applied to prevent concurrent GC from affecting this operation. .. change:: :tags: bug, sql :tickets: 6770 Fixed issue where type-specific bound parameter handlers would not be called upon in the case of using the :meth:`_sql.Insert.values` method with the Python ``None`` value; in particular, this would be noticed when using the :class:`_types.JSON` datatype as well as related PostgreSQL specific types such as :class:`_postgresql.JSONB` which would fail to encode the Python ``None`` value into JSON null, however the issue was generalized to any bound parameter handler in conjunction with this specific method of :class:`_sql.Insert`. .. change:: :tags: bug, engine :tickets: 6740 Added some guards against ``KeyError`` in the event system to accommodate the case that the interpreter is shutting down at the same time :meth:`_engine.Engine.dispose` is being called, which would cause stack trace warnings. .. change:: :tags: bug, orm, regression :tickets: 6793 Fixed critical caching issue where the ORM's persistence feature using INSERT..RETURNING would cache an incorrect query when mixing the "bulk save" and standard "flush" forms of INSERT. .. changelog:: ``` ### 1.4.21 ``` :released: July 14, 2021 .. change:: :tags: usecase, orm :tickets: 6708 Modified the approach used for history tracking of scalar object relationships that are not many-to-one, i.e. one-to-one relationships that would otherwise be one-to-many. When replacing a one-to-one value, the "old" value that would be replaced is no longer loaded immediately, and is instead handled during the flush process. This eliminates an historically troublesome lazy load that otherwise often occurs when assigning to a one-to-one attribute, and is particularly troublesome when using "lazy='raise'" as well as asyncio use cases. This change does cause a behavioral change within the :meth:`_orm.AttributeEvents.set` event, which is nonetheless currently documented, which is that the event applied to such a one-to-one attribute will no longer receive the "old" parameter if it is unloaded and the :paramref:`_orm.relationship.active_history` flag is not set. As is documented in :meth:`_orm.AttributeEvents.set`, if the event handler needs to receive the "old" value when the event fires off, the active_history flag must be established either with the event listener or with the relationship. This is already the behavior with other kinds of attributes such as many-to-one and column value references. The change additionally will defer updating a backref on the "old" value in the less common case that the "old" value is locally present in the session, but isn't loaded on the relationship in question, until the next flush occurs. If this causes an issue, again the normal :paramref:`_orm.relationship.active_history` flag can be set to ``True`` on the relationship. .. change:: :tags: usecase, sql :tickets: 6752 Added new method :meth:`_sql.HasCTE.add_cte` to each of the :func:`_sql.select`, :func:`_sql.insert`, :func:`_sql.update` and :func:`_sql.delete` constructs. This method will add the given :class:`_sql.CTE` as an "independent" CTE of the statement, meaning it renders in the WITH clause above the statement unconditionally even if it is not otherwise referenced in the primary statement. This is a popular use case on the PostgreSQL database where a CTE is used for a DML statement that runs against database rows independently of the primary statement. .. change:: :tags: bug, postgresql :tickets: 6755 Fixed issue in :meth:`_postgresql.Insert.on_conflict_do_nothing` and :meth:`_postgresql.Insert.on_conflict_do_update` where the name of a unique constraint passed as the ``constraint`` parameter would not be properly truncated for length if it were based on a naming convention that generated a too-long name for the PostgreSQL max identifier length of 63 characters, in the same way which occurs within a CREATE TABLE statement. .. change:: :tags: bug, sql :tickets: 6710 Fixed issue in CTE constructs where a recursive CTE that referred to a SELECT that has duplicate column names, which are typically deduplicated using labeling logic in 1.4, would fail to refer to the deduplicated label name correctly within the WITH clause. .. change:: :tags: bug, regression, mssql :tickets: 6697 Fixed regression where the special dotted-schema name handling for the SQL Server dialect would not function correctly if the dotted schema name were used within the ``schema_translate_map`` feature. .. change:: :tags: orm, regression :tickets: 6718 Fixed ORM regression where ad-hoc label names generated for hybrid properties and potentially other similar types of ORM-enabled expressions would usually be propagated outwards through subqueries, allowing the name to be retained in the final keys of the result set even when selecting from subqueries. Additional state is now tracked in this case that isn't lost when a hybrid is selected out of a Core select / subquery. .. change:: :tags: bug, postgresql :tickets: 6739 Fixed issue where the PostgreSQL ``ENUM`` datatype as embedded in the ``ARRAY`` datatype would fail to emit correctly in create/drop when the ``schema_translate_map`` feature were also in use. Additionally repairs a related issue where the same ``schema_translate_map`` feature would not work for the ``ENUM`` datatype in combination with a ``CAST``, that's also intrinsic to how the ``ARRAY(ENUM)`` combination works on the PostgreSQL dialect. .. change:: :tags: bug, sql, regression :tickets: 6735 Fixed regression where the :func:`_sql.tablesample` construct would fail to be executable when constructed given a floating-point sampling value not embedded within a SQL function. .. change:: :tags: bug, postgresql :tickets: 6696 Fixed issue in :meth:`_postgresql.Insert.on_conflict_do_nothing` and :meth:`_postgresql.Insert.on_conflict_do_update` where the name of a unique constraint passed as the ``constraint`` parameter would not be properly quoted if it contained characters which required quoting. .. change:: :tags: bug, regression, orm :tickets: 6698 Fixed regression caused in 1.4.19 due to :ticket:`6503` and related involving :meth:`_orm.Query.with_entities` where the new structure used would be inappropriately transferred to an enclosing :class:`_orm.Query` when making use of set operations such as :meth:`_orm.Query.union`, causing the JOIN instructions within to be applied to the outside query as well. .. change:: :tags: bug, orm, regression :tickets: 6762 Fixed regression which appeared in version 1.4.3 due to :ticket:`6060` where rules that limit ORM adaptation of derived selectables interfered with other ORM-adaptation based cases, in this case when applying adaptations for a :func:`_orm.with_polymorphic` against a mapping which uses a :func:`_orm.column_property` which in turn makes use of a scalar select that includes a :func:`_orm.aliased` object of the mapped table. .. changelog:: ``` ### 1.4.20 ``` :released: June 28, 2021 .. change:: :tags: bug, regression, orm :tickets: 6680 Fixed regression in ORM regarding an internal reconstitution step for the :func:`_orm.with_polymorphic` construct, when the user-facing object is garbage collected as the query is processed. The reconstitution was not ensuring the sub-entities for the "polymorphic" case were handled, leading to an ``AttributeError``. .. change:: :tags: usecase, sql :tickets: 6646 Add a impl parameter to :class:`_types.PickleType` constructor, allowing any arbitrary type to be used in place of the default implementation of :class:`_types.LargeBinary`. Pull request courtesy jason3gb. .. change:: :tags: bug, engine :tickets: 5348 Fixed an issue in the C extension for the :class:`_result.Row` class which could lead to a memory leak in the unlikely case of a :class:`_result.Row` object which referred to an ORM object that then was mutated to refer back to the ``Row`` itself, creating a cycle. The Python C APIs for tracking GC cycles has been added to the native :class:`_result.Row` implementation to accommodate for this case. .. change:: :tags: bug, engine :tickets: 6665 Fixed old issue where a :func:`_sql.select()` made against the token "*", which then yielded exactly one column, would fail to correctly organize the ``cursor.description`` column name into the keys of the result object. .. change:: :tags: usecase, mysql :tickets: 6659 Made a small adjustment in the table reflection feature of the MySQL dialect to accommodate for alternate MySQL-oriented databases such as TiDB which include their own "comment" directives at the end of a constraint directive within "CREATE TABLE" where the format doesn't have the additional space character after the comment, in this case the TiDB "clustered index" feature. Pull request courtesy Daniël van Eeden. .. change:: :tags: bug, schema :tickets: 6685 Fixed issue where passing ``None`` for the value of :paramref:`_schema.Table.prefixes` would not store an empty list, but rather the constant ``None``, which may be unexpected by third party dialects. The issue is revealed by a usage in recent versions of Alembic that are passing ``None`` for this value. Pull request courtesy Kai Mueller. .. change:: :tags: bug, regression, ext :tickets: 6679 Fixed regression in :mod:`sqlalchemy.ext.automap` extension such that the use case of creating an explicit mapped class to a table that is also the :paramref:`_orm.relationship.secondary` element of a :func:`_orm.relationship` that automap will be generating would emit the "overlaps" warnings introduced in 1.4 and discussed at :ref:`error_qzyx`. While generating this case from automap is still subject to the same caveats that the "overlaps" warning refers towards, as automap is intended for more ad-hoc use cases, the condition which produces the warning is disabled when a many-to-many relationship with this particular pattern is generated. .. change:: :tags: bug, regression, orm :tickets: 6678 Adjusted :meth:`_orm.Query.union` and similar set operations to be correctly compatible with the new capabilities just added in :ticket:`6661`, with SQLAlchemy 1.4.19, such that the SELECT statements rendered as elements of the UNION or other set operation will include directly mapped columns that are mapped as deferred; this both fixes a regression involving unions with multiple levels of nesting that would produce a column mismatch, and also allows the :func:`_orm.undefer` option to be used at the top level of such a :class:`_orm.Query` without having to apply the option to each of the elements within the UNION. .. change:: :tags: bug, sql, orm :tickets: 6668 Fixed the class hierarchy for the :class:`_schema.Sequence` and the more general :class:`_schema.DefaultGenerator` base, as these are "executable" as statements they need to include :class:`_sql.Executable` in their hierarchy, not just :class:`_roles.StatementRole` as was applied arbitrarily to :class:`_schema.Sequence` previously. The fix allows :class:`_schema.Sequence` to work in all ``.execute()`` methods including with :meth:`_orm.Session.execute` which was not working in the case that a :meth:`_orm.SessionEvents.do_orm_execute` handler was also established. .. change:: :tags: bug, orm :tickets: 6538 Adjusted the check in the mapper for a callable object that is used as a ``validates`` validator function or a ``reconstructor`` reconstruction function, to check for "callable" more liberally such as to accommodate objects based on fundamental attributes like ``__func__`` and ``__call___``, rather than testing for ``MethodType`` / ``FunctionType``, allowing things like cython functions to work properly. Pull request courtesy Miłosz Stypiński. .. changelog:: ``` ### 1.4.19 ``` :released: June 22, 2021 .. change:: :tags: bug, mssql :tickets: 6658 Fixed bug where the "schema_translate_map" feature would fail to function correctly in conjunction with an INSERT into a table that has an IDENTITY column, where the value of the IDENTITY column were specified in the values of the INSERT thus triggering SQLAlchemy's feature of setting IDENTITY INSERT to "on"; it's in this directive where the schema translate map would fail to be honored. .. change:: :tags: bug, sql :tickets: 6663 Fixed issue in CTE constructs mostly relevant to ORM use cases where a recursive CTE against "anonymous" labels such as those seen in ORM ``column_property()`` mappings would render in the ``WITH RECURSIVE xyz(...)`` section as their raw internal label and not a cleanly anonymized name. .. change:: :tags: mssql, change :tickets: 6503, 6253 Made improvements to the server version regexp used by the pymssql dialect to prevent a regexp overflow in case of an invalid version string. .. change:: :tags: bug, orm, regression :tickets: 6503, 6253 Fixed further regressions in the same area as that of :ticket:`6052` where loader options as well as invocations of methods like :meth:`_orm.Query.join` would fail if the left side of the statement for which the option/join depends upon were replaced by using the :meth:`_orm.Query.with_entities` method, or when using 2.0 style queries when using the :meth:`_sql.Select.with_only_columns` method. A new set of state has been added to the objects which tracks the "left" entities that the options / join were made against which is memoized when the lead entities are changed. .. change:: :tags: bug, asyncio, postgresql :tickets: 6652 Fixed bug in asyncio implementation where the greenlet adaptation system failed to propagate ``BaseException`` subclasses, most notably including ``asyncio.CancelledError``, to the exception handling logic used by the engine to invalidate and clean up the connection, thus preventing connections from being correctly disposed when a task was cancelled. .. change:: :tags: usecase, asyncio :tickets: 6583 Implemented :class:`_asyncio.async_scoped_session` to address some asyncio-related incompatibilities between :class:`_orm.scoped_session` and :class:`_asyncio.AsyncSession`, in which some methods (notably the :meth:`_asyncio.async_scoped_session.remove` method) should be used with the ``await`` keyword. .. seealso:: :ref:`asyncio_scoped_session` .. change:: :tags: usecase, mysql :tickets: 6132 Added new construct :class:`_mysql.match`, which provides for the full range of MySQL's MATCH operator including multiple column support and modifiers. Pull request courtesy Anton Kovalevich. .. seealso:: :class:`_mysql.match` .. change:: :tags: bug, postgresql, oracle :tickets: 6649 Fixed issue where the ``INTERVAL`` datatype on PostgreSQL and Oracle would produce an ``AttributeError`` when used in the context of a comparison operation against a ``timedelta()`` object. Pull request courtesy MajorDallas. .. change:: :tags: bug, mypy :tickets: 6476 Fixed issue in mypy plugin where class info for a custom declarative base would not be handled correctly on a cached mypy pass, leading to an AssertionError being raised. .. change:: :tags: bug, orm :tickets: 6661 Refined the behavior of ORM subquery rendering with regards to deferred columns and column properties to be more compatible with that of 1.3 while also providing for 1.4's newer features. As a subquery in 1.4 does not make use of loader options, including :func:`_orm.undefer`, a subquery that is against an ORM entity with deferred attributes will now render those deferred attributes that refer directly to mapped table columns, as these are needed in the outer SELECT if that outer SELECT makes use of these columns; however a deferred attribute that refers to a composed SQL expression as we normally do with :func:`_orm.column_property` will not be part of the subquery, as these can be selected explicitly if needed in the subquery. If the entity is being SELECTed from this subquery, the column expression can still render on "the outside" in terms of the derived subquery columns. This produces essentially the same behavior as when working with 1.3. However in this case the fix has to also make sure that the ``.selected_columns`` collection of an ORM-enabled :func:`_sql.select` also follows these rules, which in particular allows recursive CTEs to render correctly in this scenario, which were previously failing to render correctly due to this issue. .. change:: :tags: bug, postgresql :tickets: 6621 Fixed issue where the pool "pre ping" feature would implicitly start a transaction, which would then interfere with custom transactional flags such as PostgreSQL's "read only" mode when used with the psycopg2 driver. .. changelog:: ``` ### 1.4.18 ``` :released: June 10, 2021 .. change:: :tags: bug, orm :tickets: 6072, 6487 Clarified the current purpose of the :paramref:`_orm.relationship.bake_queries` flag, which in 1.4 is to enable or disable "lambda caching" of statements within the "lazyload" and "selectinload" loader strategies; this is separate from the more foundational SQL query cache that is used for most statements. Additionally, the lazy loader no longer uses its own cache for many-to-one SQL queries, which was an implementation quirk that doesn't exist for any other loader scenario. Finally, the "lru cache" warning that the lazyloader and selectinloader strategies could emit when handling a wide array of class/relationship combinations has been removed; based on analysis of some end-user cases, this warning doesn't suggest any significant issue. While setting ``bake_queries=False`` for such a relationship will remove this cache from being used, there's no particular performance gain in this case as using no caching vs. using a cache that needs to refresh often likely still wins out on the caching being used side. .. change:: :tags: bug, asyncio :tickets: 6575 Fixed an issue that presented itself when using the :class:`_pool.NullPool` or the :class:`_pool.StaticPool` with an async engine. This mostly affected the aiosqlite dialect. .. change:: :tags: bug, sqlite, regression :tickets: 6586 The fix for pysqlcipher released in version 1.4.3 :ticket:`5848` was unfortunately non-working, in that the new ``on_connect_url`` hook was erroneously not receiving a ``URL`` object under normal usage of :func:`_sa.create_engine` and instead received a string that was unhandled; the test suite failed to fully set up the actual conditions under which this hook is called. This has been fixed. .. change:: :tags: bug, postgresql, regression :tickets: 6581 Fixed regression where using the PostgreSQL "INSERT..ON CONFLICT" structure would fail to work with the psycopg2 driver if it were used in an "executemany" context along with bound parameters in the "SET" clause, due to the implicit use of the psycopg2 fast execution helpers which are not appropriate for this style of INSERT statement; as these helpers are the default in 1.4 this is effectively a regression. Additional checks to exclude this kind of statement from that particular extension have been added. .. change:: :tags: bug, orm, regression :tickets: 6285 Adjusted the means by which classes such as :class:`_orm.scoped_session` and :class:`_asyncio.AsyncSession` are generated from the base :class:`_orm.Session` class, such that custom :class:`_orm.Session` subclasses such as that used by Flask-SQLAlchemy don't need to implement positional arguments when they call into the superclass method, and can continue using the same argument styles as in previous releases. .. change:: :tags: bug, orm, regression :tickets: 6595 Fixed issue where query production for joinedload against a complex left hand side involving joined-table inheritance could fail to produce a correct query, due to a clause adaption issue. .. change:: :tags: bug, orm, regression, performance :tickets: 6596 Fixed regression involving how the ORM would resolve a given mapped column to a result row, where under cases such as joined eager loading, a slightly more expensive "fallback" could take place to set up this resolution due to some logic that was removed since 1.3. The issue could also cause deprecation warnings involving column resolution to be emitted when using a 1.4 style query with joined eager loading. .. change:: :tags: bug, orm :tickets: 6591 Fixed issue in experimental "select ORM objects from INSERT/UPDATE" use case where an error was raised if the statement were against a single-table-inheritance subclass. .. change:: :tags: bug, asyncio :tickets: 6592 Added ``asyncio.exceptions.TimeoutError``, ``asyncio.exceptions.CancelledError`` as so-called "exit exceptions", a class of exceptions that include things like ``GreenletExit`` and ``KeyboardInterrupt``, which are considered to be events that warrant considering a DBAPI connection to be in an unusable state where it should be recycled. .. change:: :tags: bug, orm :tickets: 6400 The warning that's emitted for :func:`_orm.relationship` when multiple relationships would overlap with each other as far as foreign key attributes written towards, now includes the specific "overlaps" argument to use for each warning in order to silence the warning without changing the mapping. .. change:: :tags: usecase, asyncio :tickets: 6319 Implemented a new regist