[oracle] [bug] [performance] [py2k] Fixed performance regression caused by the fix for #3937 where
cx_Oracle as of version 5.3 dropped the .UNICODE symbol from its
namespace, which was interpreted as cx_Oracle’s “WITH_UNICODE” mode being
turned on unconditionally, which invokes functions on the SQLAlchemy
side which convert all strings to unicode unconditionally and causing
a performance impact. In fact, per cx_Oracle’s author the
“WITH_UNICODE” mode has been removed entirely as of 5.1, so the expensive unicode
conversion functions are no longer necessary and are disabled if
cx_Oracle 5.1 or greater is detected under Python 2. The warning against
“WITH_UNICODE” mode that was removed under #3937 is also restored.¶
References: #4035
[orm] [bug] Fixed bug in Session.bulk_update_mappings() where an alternate-named
primary key attribute would not track properly into the UPDATE statement.¶
References: #3849
[orm] [bug] Fixed bug where joined eager loading would fail for a polymorphically- loaded mapper, where the polymorphic_on was set to an un-mapped expression such as a CASE expression.¶
References: #3800
[orm] [bug] Fixed bug where the ArgumentError raised for an invalid bind
sent to a Session via Session.bind_mapper(),
Session.bind_table(),
or the constructor would fail to be correctly raised.¶
References: #3798
[orm] [bug] Fixed bug in Session.bulk_save() where an UPDATE would
not function correctly in conjunction with a mapping that
implements a version id counter.¶
References: #3781
[orm] [bug] Fixed bug where the Mapper.attrs,
Mapper.all_orm_descriptors and other derived attributes would
fail to refresh when mapper properties or other ORM constructs were
added to the mapper/class after these accessors were first called.¶
References: #3778
[mssql] [bug] Changed the query used to get “default schema name”, from one that queries the database principals table to using the “schema_name()” function, as issues have been reported that the former system was unavailable on the Azure Data Warehouse edition. It is hoped that this will finally work across all SQL Server versions and authentication styles.¶
References: #3810
[mssql] [bug] Updated the server version info scheme for pyodbc to use SQL Server SERVERPROPERTY(), rather than relying upon pyodbc.SQL_DBMS_VER, which continues to be unreliable particularly with FreeTDS.¶
References: #3814
[mssql] [bug] Added error code 20017 “unexpected EOF from the server” to the list of disconnect exceptions that result in a connection pool reset. Pull request courtesy Ken Robbins.¶
[mssql] [bug] Fixed bug in pyodbc dialect (as well as in the mostly non-working adodbapi dialect) whereby a semicolon present in the password or username fields could be interpreted as a separator for another token; the values are now quoted when semicolons are present.¶
References: #3762
[sql] [bug] Fixed bug in Table where the internal method
_reset_exported() would corrupt the state of the object. This
method is intended for selectable objects and is called by the ORM
in some cases; an erroneous mapper configuration would could lead the
ORM to call this on a Table object.¶
References: #3755
[mysql] [bug] Added support for parsing MySQL/Connector boolean and integer arguments within the URL query string: connection_timeout, connect_timeout, pool_size, get_warnings, raise_on_warnings, raw, consume_results, ssl_verify_cert, force_ipv6, pool_reset_session, compress, allow_local_infile, use_pure.¶
References: #3787
[engine] [bug] [postgresql] Fixed bug in cross-schema foreign key reflection in conjunction
with the MetaData.schema argument, where a referenced
table that is present in the “default” schema would fail since there
would be no way to indicate a Table that has “blank” for
a schema. The special symbol schema.BLANK_SCHEMA has been
added as an available value for Table.schema and
Sequence.schema, indicating that the schema name
should be forced to be None even if MetaData.schema
is specified.¶
References: #3716
[sql] [bug] Fixed issue in SQL math negation operator where the type of the expression would no longer be the numeric type of the original. This would cause issues where the type determined result set behaviors.¶
References: #3735
[sql] [bug] Fixed bug whereby the __getstate__ / __setstate__
methods for sqlalchemy.util.Properties were
non-working due to the transition in the 1.0 series to __slots__.
The issue potentially impacted some third-party applications.
Pull request courtesy Pieter Mulder.¶
References: #3728
[sql] [bug] FromClause.count() is pending deprecation for 1.1. This function
makes use of an arbitrary column in the table and is not reliable;
for Core use, func.count() should be preferred.¶
References: #3724
[sql] [bug] Fixed bug in CTE structure which would cause it to not
clone properly when a union was used, as is common in a recursive
CTE. The improper cloning would cause errors when the CTE is used
in various ORM contexts such as that of a column_property().¶
References: #3722
[sql] [bug] Fixed bug whereby Table.tometadata() would make a duplicate
UniqueConstraint for each Column object that
featured the unique=True parameter.¶
References: #3721
[postgresql] [bug] Fixed bug whereby TypeDecorator and Variant
types were not deeply inspected enough by the PostgreSQL dialect
to determine if SMALLSERIAL or BIGSERIAL needed to be rendered
rather than SERIAL.¶
References: #3739
[oracle] [bug] Fixed bug in Select.with_for_update.of, where the Oracle
“rownum” approach to LIMIT/OFFSET would fail to accommodate for the
expressions inside the “OF” clause, which must be stated at the topmost
level referring to expression within the subquery. The expressions are
now added to the subquery if needed.¶
References: #3741
[orm] [bug] Fixed bug in “evaluate” strategy of Query.update() and
Query.delete() which would fail to accommodate a bound
parameter with a “callable” value, as which occurs when filtering
by a many-to-one equality expression along a relationship.¶
References: #3700
[orm] [bug] Fixed bug whereby the event listeners used for backrefs could be inadvertently applied multiple times, when using a deep class inheritance hierarchy in conjunction with multiple mapper configuration steps.¶
References: #3710
[orm] [bug] Fixed bug whereby passing a text() construct to the
Query.group_by() method would raise an error, instead
of interpreting the object as a SQL fragment.¶
References: #3706
[orm] [bug] Anonymous labeling is applied to a func construct that is
passed to column_property(), so that if the same attribute
is referred to as a column expression twice the names are de-duped,
thus avoiding “ambiguous column” errors. Previously, the
.label(None) would need to be applied in order for the name
to be de-anonymized.¶
References: #3663
[orm] [bug] Fixed regression appearing in the 1.0 series in ORM loading where the
exception raised for an expected column missing would incorrectly
be a NoneType error, rather than the expected
NoSuchColumnError.¶
References: #3658
[sql] [bug] Fixed bug where when using case_sensitive=False with an
Engine, the result set would fail to correctly accommodate
for duplicate column names in the result set, causing an error
when the statement is executed in 1.0, and preventing the
“ambiguous column” exception from functioning in 1.1.¶
References: #3690
[sql] [bug] Fixed bug where the negation of an EXISTS expression would not be properly typed as boolean in the result, and also would fail to be anonymously aliased in a SELECT list as is the case with a non-negated EXISTS construct.¶
References: #3682
[sql] [bug] Fixed bug where “unconsumed column names” exception would fail to
be raised in the case where Insert.values() were called
with a list of parameter mappings, instead of a single mapping
of parameters. Pull request courtesy Athena Yao.¶
References: #3666
[mssql] [bug] Fixed bug where by ROW_NUMBER OVER clause applied for OFFSET selects in SQL Server would inappropriately substitute a plain column from the local statement that overlaps with a label name used by the ORDER BY criteria of the statement.¶
References: #3711
[mssql] [bug] [oracle] Fixed regression appearing in the 1.0 series which would cause the Oracle
and SQL Server dialects to incorrectly account for result set columns
when these dialects would wrap a SELECT in a subquery in order to
provide LIMIT/OFFSET behavior, and the original SELECT statement
referred to the same column multiple times, such as a column and
a label of that same column. This issue is related
to #3658 in that when the error occurred, it would also
cause a NoneType error, rather than reporting that it couldn’t
locate a column.¶
References: #3657
[oracle] [bug] Fixed a bug in the cx_Oracle connect process that caused a TypeError when the either the user, password or dsn was empty. This prevented external authentication to Oracle databases, and prevented connecting to the default dsn. The connect string oracle:// now logs into the default dsn using the Operating System username, equivalent to connecting using ‘/’ with sqlplus.¶
References: #3705
[oracle] [bug] Fixed a bug in the result proxy used mainly by Oracle when binary and other LOB types are in play, such that when query / statement caching were used, the type-level result processors, notably that required by the binary type itself but also any other processor, would become lost after the first run of the statement due to it being removed from the cached result metadata.¶
References: #3699
[bug] [examples] Changed the “directed graph” example to no longer consider integer identifiers of nodes as significant; the “higher” / “lower” references now allow mutual edges in both directions.¶
References: #3698
[bug] [py3k] Fixed bug in “to_list” conversion where a single bytes object
would be turned into a list of individual characters. This would
impact among other things using the Query.get() method
on a primary key that’s a bytes object.¶
References: #3660
[orm] [bug] Fixed bug in Session.merge() where an object with a composite
primary key that has values for some but not all of the PK fields
would emit a SELECT statement leaking the internal NEVER_SET symbol
into the query, rather than detecting that this object does not have
a searchable primary key and no SELECT should be emitted.¶
References: #3647
[orm] [bug] Fixed regression since 0.9 where the 0.9 style loader options
system failed to accommodate for multiple undefer_group()
loader options in a single query. Multiple undefer_group()
options will now be taken into account even against the same
entity.¶
References: #3623
[engine] [bug] [mysql] Revisiting #2696, first released in 1.0.10, which attempts to work around Python 2’s lack of exception context reporting by emitting a warning for an exception that was interrupted by a second exception when attempting to roll back the already-failed transaction; this issue continues to occur for MySQL backends in conjunction with a savepoint that gets unexpectedly lost, which then causes a “no such savepoint” error when the rollback is attempted, obscuring what the original condition was.
The approach has been generalized to the Core “safe
reraise” function which takes place across the ORM and Core in any
place that a transaction is being rolled back in response to an error
which occurred trying to commit, including the context managers
provided by Session and Connection, and taking
place for operations such as a failure on “RELEASE SAVEPOINT”.
Previously, the fix was only in place for a specific path within
the ORM flush/commit process; it now takes place for all transactional
context managers as well.
References: #2696
[sql] [bug] Fixed issue where the “literal_binds” flag was not propagated
for expression.insert(), expression.update() or
expression.delete() constructs when compiled to string
SQL. Pull request courtesy Tim Tate.¶
References: #3643
[sql] [bug] Fixed issue where inadvertent use of the Python __contains__
override with a column expression (e.g. by using 'x' in col)
would cause an endless loop in the case of an ARRAY type, as Python
defers this to __getitem__ access which never raises for this
type. Overall, all use of __contains__ now raises
NotImplementedError.¶
References: #3642
[sql] [bug] Fixed bug in Table metadata construct which appeared
around the 0.9 series where adding columns to a Table
that was unpickled would fail to correctly establish the
Column within the ‘c’ collection, leading to issues in
areas such as ORM configuration. This could impact use cases such
as extend_existing and others.¶
References: #3632
[postgresql] [bug] Fixed bug in expression.text() construct where a double-colon
expression would not escape properly, e.g. some\:\:expr, as is most
commonly required when rendering PostgreSQL-style CAST expressions.¶
References: #3644
[mssql] [bug] Fixed the syntax of the extract() function when used on
MSSQL against a datetime value; the quotes around the keyword
are removed. Pull request courtesy Guillaume Doumenc.¶
References: #3624
[mssql] [bug] [firebird] Fixed 1.0 regression where the eager fetch of cursor.rowcount was
no longer called for an UPDATE or DELETE statement emitted via plain
text or via the text() construct, affecting those drivers
that erase cursor.rowcount once the cursor is closed such as SQL
Server ODBC and Firebird drivers.¶
References: #3622
[orm] [bug] Fixed regression caused in 1.0.10 by the fix for #3593 where the check added for a polymorphic joinedload from a poly_subclass->class->poly_baseclass connection would fail for the scenario of class->poly_subclass->class.¶
References: #3611
[orm] [bug] Fixed bug where Session.bulk_update_mappings() and related
would not bump a version id counter when in use. The experience
here is still a little rough as the original version id is required
in the given dictionaries and there’s not clean error reporting
on that yet.¶
References: #3610
[orm] [bug] Major fixes to the Mapper.eager_defaults flag, this
flag would not be honored correctly in the case that multiple
UPDATE statements were to be emitted, either as part of a flush
or a bulk update operation. Additionally, RETURNING
would be emitted unnecessarily within update statements.¶
References: #3609
[orm] [bug] Fixed bug where use of the Query.select_from() method would
cause a subsequent call to the Query.with_parent() method to
fail.¶
References: #3606
[sql] [bug] Fixed bug in Update.return_defaults() which would cause all
insert-default holding columns not otherwise included in the SET
clause (such as primary key cols) to get rendered into the RETURNING
even though this is an UPDATE.¶
References: #3609
[mysql] [bug] An adjustment to the regular expression used to parse MySQL views, such that we no longer assume the “ALGORITHM” keyword is present in the reflected view source, as some users have reported this not being present in some Amazon RDS environments.¶
References: #3613
[mysql] [bug] Added new reserved words for MySQL 5.7 to the MySQL dialect, including ‘generated’, ‘optimizer_costs’, ‘stored’, ‘virtual’. Pull request courtesy Hanno Schlichting.¶
[bug] [ext] Further fixes to #3605, pop method on MutableDict,
where the “default” argument was not included.¶
References: #3605
[bug] [ext] Fixed bug in baked loader system where the systemwide monkeypatch
for setting up baked lazy loaders would interfere with other
loader strategies that rely on lazy loading as a fallback, e.g.
joined and subquery eager loaders, leading to IndexError
exceptions at mapper configuration time.¶
References: #3612
[orm] [bug] Fixed issue where post_update on a many-to-one relationship would fail to emit an UPDATE in the case where the attribute were set to None and not previously loaded.¶
References: #3599
[orm] [bug] Fixed bug which is actually a regression that occurred between versions 0.8.0 and 0.8.1, due #2714. The case where joined eager loading needs to join out over a subclass-bound relationship when “with_polymorphic” were also used would fail to join from the correct entity.¶
References: #3593
[orm] [bug] Fixed joinedload bug which would occur when a. the query includes limit/offset criteria that forces a subquery b. the relationship uses “secondary” c. the primaryjoin of the relationship refers to a column that is either not part of the primary key, or is a PK col in a joined-inheritance subclass table that is under a different attribute name than the parent table’s primary key column d. the query defers the columns that are present in the primaryjoin, typically via not being included in load_only(); the necessary column(s) would not be present in the subquery and produce invalid SQL.¶
References: #3592
[orm] [bug] A rare case which occurs when a Session.rollback() fails in the
scope of a Session.flush() operation that’s raising an
exception, as has been observed in some MySQL SAVEPOINT cases, prevents
the original database exception from being observed when it was
emitted during flush, but only on Py2K because Py2K does not support
exception chaining; on Py3K the originating exception is chained. As
a workaround, a warning is emitted in this specific case showing at
least the string message of the original database error before we
proceed to raise the rollback-originating exception.¶
References: #2696
[bug] [declarative] [orm] Fixed bug where in Py2K a unicode literal would not be accepted as the
string name of a class or other argument within declarative using
backref() on relationship(). Pull request courtesy
Nils Philippsen.¶
[sql] [feature] Added support for parameter-ordered SET clauses in an UPDATE
statement. This feature is available by passing the
preserve_parameter_order
flag either to the core Update construct or alternatively
adding it to the Query.update.update_args dictionary at
the ORM-level, also passing the parameters themselves as a list of 2-tuples.
Thanks to Gorka Eguileor for implementation and tests.
See also
[sql] [bug] Fixed issue within the Insert.from_select() construct whereby
the Select construct would have its ._raw_columns
collection mutated in-place when compiling the Insert
construct, when the target Table has Python-side defaults.
The Select construct would compile standalone with the
erroneous column present subsequent to compilation of the
Insert, and the Insert statement itself would
fail on a second compile attempt due to duplicate bound parameters.¶
References: #3603
[sql] [bug] [postgresql] Fixed bug where CREATE TABLE with a no-column table, but a constraint such as a CHECK constraint would render an erroneous comma in the definition; this scenario can occur such as with a PostgreSQL INHERITS table that has no columns of its own.¶
References: #3598
[postgresql] [bug] Fixed issue where the “FOR UPDATE OF” PostgreSQL-specific SELECT modifier would fail if the referred table had a schema qualifier; PG needs the schema name to be omitted. Pull request courtesy Diana Clarke.¶
References: #3573
[postgresql] [bug] Fixed bug where some varieties of SQL expression passed to the
“where” clause of postgresql.ExcludeConstraint would fail
to be accepted correctly. Pull request courtesy aisch.¶
[postgresql] [bug] Fixed the .python_type attribute of postgresql.INTERVAL
to return datetime.timedelta in the same way as that of
types.Interval.python_type, rather than raising
NotImplementedError.¶
References: #3571
[mysql] [bug] Fixed bug in MySQL reflection where the “fractional sections portion”
of the mysql.DATETIME, mysql.TIMESTAMP and
mysql.TIME types would be incorrectly placed into the
timezone attribute, which is unused by MySQL, instead of the
fsp attribute.¶
References: #3602
[mssql] [bug] Added the error “20006: Write to the server failed” to the list of disconnect errors for the pymssql driver, as this has been observed to render a connection unusable.¶
References: #3585
[mssql] [bug] A descriptive ValueError is now raised in the event that SQL server returns an invalid date or time format from a DATE or TIME column, rather than failing with a NoneType error. Pull request courtesy Ed Avis.¶
[mssql] [bug] Fixed issue where DDL generated for the MSSQL types DATETIME2, TIME and DATETIMEOFFSET with a precision of “zero” would not generate the precision field. Pull request courtesy Jacobo de Vera.¶
[bug] [ext] Added support for the dict.pop() and dict.popitem() methods
to the mutable.MutableDict class.¶
References: #3605
[bug] [py3k] Updates to internal getargspec() calls, some py36-related fixture updates, and alterations to two iterators to “return” instead of raising StopIteration, to allow tests to pass without errors or warnings on Py3.5, Py3.6, pull requests courtesy Jacob MacDonald, Luri de Silvio, and Phil Jones.¶
[bug] [ext] Fixed an issue in baked queries where the .get() method, used either directly or within lazy loads, didn’t consider the mapper’s “get clause” as part of the cache key, causing bound parameter mismatches if the clause got re-generated. This clause is cached by mappers on the fly but in highly concurrent scenarios may be generated more than once when first accessed.¶
References: #3597
[change] [tests] The ORM and Core tutorials, which have always been in doctest format, are now exercised within the normal unit test suite in both Python 2 and Python 3.¶
[orm] [feature] Added new method Query.one_or_none(); same as
Query.one() but returns None if no row found. Pull request
courtesy esiegerman.¶
[orm] [bug] [postgresql] Fixed regression in 1.0 where new feature of using “executemany” for UPDATE statements in the ORM (e.g. UPDATE statements are now batched with executemany() in a flush) would break on PostgreSQL and other RETURNING backends when using server-side version generation schemes, as the server side value is retrieved via RETURNING which is not supported with executemany.¶
References: #3556
[orm] [bug] Fixed rare TypeError which could occur when stringifying certain kinds of internal column loader options within internal logging.¶
References: #3539
[orm] [bug] Fixed bug in Session.bulk_save_objects() where a mapped
column that had some kind of “fetch on update” value and was not
locally present in the given object would cause an AttributeError
within the operation.¶
References: #3525
[orm] [bug] Fixed 1.0 regression where the “noload” loader strategy would fail to function for a many-to-one relationship. The loader used an API to place “None” into the dictionary which no longer actually writes a value; this is a side effect of #3061.¶
References: #3510
[sql] [bug] Fixed regression in 1.0-released default-processor for multi-VALUES insert statement, #3288, where the column type for the default-holding column would not be propagated to the compiled statement in the case where the default was being used, leading to bind-level type handlers not being invoked.¶
References: #3520
[postgresql] [bug] An adjustment to the new PostgreSQL feature of reflecting storage
options and USING of #3455 released in 1.0.6,
to disable the feature for PostgreSQL versions < 8.2 where the
reloptions column is not provided; this allows Amazon Redshift
to again work as it is based on an 8.0.x version of PostgreSQL.
Fix courtesy Pete Hollobon.¶
[oracle] [bug] [py3k] Fixed support for cx_Oracle version 5.2, which was tripping up SQLAlchemy’s version detection under Python 3 and inadvertently not using the correct unicode mode for Python 3. This would cause issues such as bound variables mis-interpreted as NULL and rows silently not being returned.¶
This change is also backported to: 0.7.0b1
References: #3491
[oracle] [bug] Fixed bug in Oracle dialect where reflection of tables and other
symbols with names quoted to force all-lower-case would not be
identified properly in reflection queries. The quoted_name
construct is now applied to incoming symbol names that detect as
forced into all-lower-case within the “name normalize” process.¶
References: #3548
[feature] [ext] Added the AssociationProxy.info parameter to the
AssociationProxy constructor, to suit the
AssociationProxy.info accessor that was added in
#2971. This is possible because AssociationProxy
is constructed explicitly, unlike a hybrid which is constructed
implicitly via the decorator syntax.¶
References: #3551
[bug] [examples] Fixed two issues in the “history_meta” example where history tracking could encounter empty history, and where a column keyed to an alternate attribute name would fail to track properly. Fixes courtesy Alex Fraser.¶
[bug] [sybase] Fixed two issues regarding Sybase reflection, allowing tables without primary keys to be reflected as well as ensured that a SQL statement involved in foreign key detection is pre-fetched up front to avoid driver issues upon nested queries. Fixes here courtesy Eugene Zapolsky; note that we cannot currently test Sybase to locally verify these changes.¶
[engine] [bug] Fixed critical issue whereby the pool “checkout” event handler
may be called against a stale connection without the “connect”
event handler having been called, in the case where the pool
attempted to reconnect after being invalidated and failed; the stale
connection would remain present and would be used on a subsequent
attempt. This issue has a greater impact in the 1.0 series subsequent
to 1.0.2, as it also delivers a blanked-out .info dictionary to
the event handler; prior to 1.0.2 the .info dictionary is still
the previous one.¶
This change is also backported to: 0.7.0b1
References: #3497
[misc] [bug] Fixed an issue where a particular base class within utils
didn’t implement __slots__, and therefore meant all subclasses
of that class didn’t either, negating the rationale for __slots__
to be in use. Didn’t cause any issue except on IronPython
which apparently does not implement __slots__ behavior compatibly
with cPython.¶
References: #3494
[orm] [bug] Fixed 1.0 regression where value objects that override
__eq__() to return a non-boolean-capable object, such as
some geoalchemy types as well as numpy types, were being tested
for bool() during a unit of work update operation, where in
0.9 the return value of __eq__() was tested against “is True”
to guard against this.¶
References: #3469
[orm] [bug] Fixed 1.0 regression where a “deferred” attribute would not populate correctly if it were loaded within the “optimized inheritance load”, which is a special SELECT emitted in the case of joined table inheritance used to populate expired or unloaded attributes against a joined table without loading the base table. This is related to the fact that SQLA 1.0 no longer guesses about loading deferred columns and must be directed explicitly.¶
References: #3468
[orm] [bug] Fixed 1.0 regression where the “parent entity” of a synonym-
mapped attribute on top of an aliased() object would
resolve to the original mapper, not the aliased()
version of it, thereby causing problems for a Query
that relies on this attribute (e.g. it’s the only representative
attribute given in the constructor) to figure out the correct FROM
clause for the query.¶
References: #3466
[bug] [declarative] [orm] Fixed bug in AbstractConcreteBase extension where
a column setup on the ABC base which had a different attribute
name vs. column name would not be correctly mapped on the final
base class. The failure on 0.9 would be silent whereas on
1.0 it raised an ArgumentError, so may not have been noticed
prior to 1.0.¶
References: #3480
[engine] [bug] Fixed regression where new methods on ResultProxy used
by the ORM Query object (part of the performance
enhancements of #3175) would not raise the “this result
does not return rows” exception in the case where the driver
(typically MySQL) fails to generate cursor.description correctly;
an AttributeError against NoneType would be raised instead.¶
References: #3481
[engine] [bug] Fixed regression where ResultProxy.keys() would return
un-adjusted internal symbol names for “anonymous” labels, which
are the “foo_1” types of labels we see generated for SQL functions
without labels and similar. This was a side effect of the
performance enhancements implemented as part of #918.¶
References: #3483
[sql] [feature] Added a ColumnElement.cast() method which performs the same
purpose as the standalone cast() function. Pull request
courtesy Sebastian Bank.¶
References: #3459
[sql] [bug] Fixed bug where coercion of literal True or False constant
in conjunction with and_() or or_() would fail
with an AttributeError.¶
References: #3490
[sql] [bug] Fixed potential issue where a custom subclass
of FunctionElement or other column element that incorrectly
states ‘None’ or any other invalid object as the .type
attribute will report this exception instead of recursion overflow.¶
References: #3485
[sql] [bug] Fixed bug where the modulus SQL operator wouldn’t work in reverse
due to a missing __rmod__ method. Pull request courtesy
dan-gittik.¶
[orm] [bug] Fixed a major regression in the 1.0 series where the version_id_counter feature would cause an object’s version counter to be incremented when there was no net change to the object’s row, but instead an object related to it via relationship (e.g. typically many-to-one) were associated or de-associated with it, resulting in an UPDATE statement that updates the object’s version counter and nothing else. In the use case where the relatively recent “server side” and/or “programmatic/conditional” version counter feature were used (e.g. setting version_id_generator to False), the bug could cause an UPDATE without a valid SET clause to be emitted.¶
References: #3465
[orm] [bug] Fixed 1.0 regression where the enhanced behavior of single-inheritance joins of #3222 takes place inappropriately for a JOIN along explicit join criteria with a single-inheritance subclass that does not make use of any discriminator, resulting in an additional “AND NULL” clause.¶
References: #3462
[orm] [bug] Fixed bug in new Session.bulk_update_mappings() feature where
the primary key columns used in the WHERE clause to locate the row
would also be included in the SET clause, setting their value to
themselves unnecessarily. Pull request courtesy Patrick Hayes.¶
References: #3451
[orm] [bug] Fixed an unexpected-use regression whereby custom Comparator
objects that made use of the __clause_element__() method and
returned an object that was an ORM-mapped
InstrumentedAttribute and not explicitly a
ColumnElement would fail to be correctly
handled when passed as an expression to Session.query().
The logic in 0.9 happened to succeed on this, so this use case is now
supported.¶
References: #3448
[sql] [bug] Fixed a bug where clause adaption as applied to a Label
object would fail to accommodate the labeled SQL expression
in all cases, such that any SQL operation that made use of
Label.self_group() would use the original unadapted
expression. One effect of this would be that an ORM aliased()
construct would not fully accommodate attributes mapped by
column_property, such that the un-aliased table could
leak out when the property were used in some kinds of SQL
comparisons.¶
References: #3445
[postgresql] [feature] Added support for storage parameters under CREATE INDEX, using
a new keyword argument postgresql_with. Also added support for
reflection to support both the postgresql_with flag as well
as the postgresql_using flag, which will now be set on
Index objects that are reflected, as well present
in a new “dialect_options” dictionary in the result of
Inspector.get_indexes(). Pull request courtesy Pete Hollobon.
See also
References: #3455
[postgresql] [feature] Added new execution option max_row_buffer which is interpreted
by the psycopg2 dialect when the stream_results option is
used, which sets a limit on the size of the row buffer that may be
allocated. This value is also provided based on the integer
value sent to Query.yield_per(). Pull request courtesy
mcclurem.¶
[postgresql] [bug] [pypy] Re-fixed this issue first released in 1.0.5 to fix psycopg2cffi JSONB support once again, as they suddenly switched on unconditional decoding of JSONB types in version 2.7.1. Version detection now specifies 2.7.1 as where we should expect the DBAPI to do json encoding for us.¶
References: #3439
[postgresql] [bug] Repaired the ExcludeConstraint construct to support common
features that other objects like Index now do, that
the column expression may be specified as an arbitrary SQL
expression such as cast or text.¶
References: #3454
[mssql] [bug] Fixed issue when using VARBINARY type in conjunction with
an INSERT of NULL + pyodbc; pyodbc requires a special
object be passed in order to persist NULL. As the VARBINARY
type is now usually the default for LargeBinary due to
#3039, this issue is partially a regression in 1.0.
The pymssql driver appears to be unaffected.¶
References: #3464
[orm] [feature] Added new event InstanceEvents.refresh_flush(), invoked
when an INSERT or UPDATE level default value fetched via RETURNING
or Python-side default is invoked within the flush process. This
is to provide a hook that is no longer present as a result of
#3167, where attribute and validation events are no longer
called within the flush process.¶
References: #3427
[orm] [bug] The “lightweight named tuple” used when a Query returns
rows failed to implement __slots__ correctly such that it still
had a __dict__. This is resolved, but in the extremely
unlikely case someone was assigning values to the returned tuples,
that will no longer work.¶
References: #3420
[engine] [feature] Added new engine event ConnectionEvents.engine_disposed().
Called after the Engine.dispose() method is called.¶
[engine] [feature] Adjustments to the engine plugin hook, such that the
URL.get_dialect() method will continue to return the
ultimate Dialect object when a dialect plugin is used,
without the need for the caller to be aware of the
Dialect.get_dialect_cls() method.¶
References: #3379
[engine] [bug] Fixed bug where known boolean values used by
engine_from_config() were not being parsed correctly;
these included pool_threadlocal and the psycopg2 argument
use_native_unicode.¶
References: #3435
[engine] [bug] Added support for the case of the misbehaving DBAPI that has
pep-249 exception names linked to exception classes of an entirely
different name, preventing SQLAlchemy’s own exception wrapping from
wrapping the error appropriately.
The SQLAlchemy dialect in use needs to implement a new
accessor DefaultDialect.dbapi_exception_translation_map
to support this feature; this is implemented now for the py-postgresql
dialect.¶
References: #3421
[engine] [bug] Fixed bug involving the case when pool checkout event handlers are used and connection attempts are made in the handler itself which fail, the owning connection record would not be freed until the stack trace of the connect error itself were freed. For the case where a test pool of only a single connection were used, this means the pool would be fully checked out until that stack trace were freed. This mostly impacts very specific debugging scenarios and is unlikely to have been noticeable in any production application. The fix applies an explicit checkin of the record before re-raising the caught exception.¶
References: #3419
[sql] [feature] Added official support for a CTE used by the SELECT present
inside of Insert.from_select(). This behavior worked
accidentally up until 0.9.9, when it no longer worked due to
unrelated changes as part of #3248. Note that this
is the rendering of the WITH clause after the INSERT, before the
SELECT; the full functionality of CTEs rendered at the top
level of INSERT, UPDATE, DELETE is a new feature targeted for a
later release.¶
This change is also backported to: 0.9.10
References: #3418
[postgresql] [bug] [pypy] Repaired some typing and test issues related to the pypy psycopg2cffi dialect, in particular that the current 2.7.0 version does not have native support for the JSONB type. The version detection for psycopg2 features has been tuned into a specific sub-version for psycopg2cffi. Additionally, test coverage has been enabled for the full series of psycopg2 features under psycopg2cffi.¶
References: #3439
[mssql] [bug] Added a new dialect flag to the MSSQL dialect
legacy_schema_aliasing which when set to False will disable a
very old and obsolete behavior, that of the compiler’s
attempt to turn all schema-qualified table names into alias names,
to work around old and no longer locatable issues where SQL
server could not parse a multi-part identifier name in all
circumstances. The behavior prevented more
sophisticated statements from working correctly, including those which
use hints, as well as CRUD statements that embed correlated SELECT
statements. Rather than continue to repair the feature to work
with more complex statements, it’s better to just disable it
as it should no longer be needed for any modern SQL server
version. The flag defaults to True for the 1.0.x series, leaving
current behavior unchanged for this version series. In the 1.1
series, it will default to False. For the 1.0 series,
when not set to either value explicitly, a warning is emitted
when a schema-qualified table is first used in a statement, which
suggests that the flag be set to False for all modern SQL Server
versions.
See also
[feature] [ext] Added support for *args to be passed to the baked query
initial callable, in the same way that *args are supported
for the BakedQuery.add_criteria() and
BakedQuery.with_criteria() methods. Initial PR courtesy
Naoki INADA.¶
[feature] [ext] Added a new semi-public method to MutableBase
MutableBase._get_listen_keys(). Overriding this method
is needed in the case where a MutableBase subclass needs
events to propagate for attribute keys other than the key to which
the mutable type is associated with, when intercepting the
InstanceEvents.refresh() or
InstanceEvents.refresh_flush() events. The current example of
this is composites using MutableComposite.¶
References: #3427
[bug] [ext] Fixed regression in the sqlalchemy.ext.mutable extension
as a result of the bugfix for #3167,
where attribute and validation events are no longer
called within the flush process. The mutable
extension was relying upon this behavior in the case where a column
level Python-side default were responsible for generating the new value
on INSERT or UPDATE, or when a value were fetched from the RETURNING
clause for “eager defaults” mode. The new value would not be subject
to any event when populated and the mutable extension could not
establish proper coercion or history listening. A new event
InstanceEvents.refresh_flush() is added which the mutable
extension now makes use of for this use case.¶
References: #3427
[orm] [bug] Fixed unexpected-use regression where in the odd case that the
primaryjoin of a relationship involved comparison to an unhashable
type such as an HSTORE, lazy loads would fail due to a hash-oriented
check on the statement parameters, modified in 1.0 as a result of
#3061 to use hashing and modified in #3368
to occur in cases more common than “load on pending”.
The values are now checked for the __hash__ attribute beforehand.¶
References: #3416
[orm] [bug] Liberalized an assertion that was added as part of #3347
to protect against unknown conditions when splicing inner joins
together within joined eager loads with innerjoin=True; if
some of the joins use a “secondary” table, the assertion needs to
unwrap further joins in order to pass.¶
[orm] [bug] Repaired / added to tests yet more expressions that were reported
as failing with the new ‘entity’ key value added to
Query.column_descriptions, the logic to discover the “from”
clause is again reworked to accommodate columns from aliased classes,
as well as to report the correct value for the “aliased” flag in these
cases.¶
[schema] [bug] Fixed bug in enhanced constraint-attachment logic introduced in
#3341 where in the unusual case of a constraint that refers
to a mixture of Column objects and string column names
at the same time, the auto-attach-on-column-attach logic will be
skipped; for the constraint to be auto-attached in this case,
all columns must be assembled on the target table up front.
Added a new section to the migration document regarding the
original feature as well as this change.
References: #3411
[bug] [ext] Fixed bug where when using extended attribute instrumentation system,
the correct exception would not be raised when class_mapper()
were called with an invalid input that also happened to not
be weak referencable, such as an integer.¶
This change is also backported to: 0.9.10
References: #3408
[bug] [pypy] [tests] Fixed an import that prevented “pypy setup.py test” from working correctly.¶
This change is also backported to: 0.9.10
References: #3406
[orm] [bug] [pypy] Fixed regression from 0.9.10 prior to release due to #3349
where the check for query state on Query.update() or
Query.delete() compared the empty tuple to itself using is,
which fails on PyPy to produce True in this case; this would
erronously emit a warning in 0.9 and raise an exception in 1.0.¶
References: #3405
[orm] [bug] Fixed regression from 0.9.10 prior to release where the new addition
of entity to the Query.column_descriptions accessor
would fail if the target entity was produced from a core selectable
such as a Table or CTE object.¶
[orm] [bug] Fixed regression within the flush process when an attribute were
set to a SQL expression for an UPDATE, and the SQL expression when
compared to the previous value of the attribute would produce a SQL
comparison other than == or !=, the exception “Boolean value
of this clause is not defined” would raise. The fix ensures that
the unit of work will not interpret the SQL expression in this way.¶
References: #3402
[orm] [bug] Fixed unexpected use regression due to #2992 where
textual elements placed
into the Query.order_by() clause in conjunction with joined
eager loading would be added to the columns clause of the inner query
in such a way that they were assumed to be table-bound column names,
in the case where the joined eager load needs to wrap the query
in a subquery to accommodate for a limit/offset.
Originally, the behavior here was intentional, in that a query such
as query(User).order_by('name').limit(1)
would order by user.name even if the query was modified by
joined eager loading to be within a subquery, as 'name' would
be interpreted as a symbol to be located within the FROM clauses,
in this case User.name, which would then be copied into the
columns clause to ensure it were present for ORDER BY. However, the
feature fails to anticipate the case where order_by("name") refers
to a specific label name present in the local columns clause already
and not a name bound to a selectable in the FROM clause.
Beyond that, the feature also fails for deprecated cases such as
order_by("name desc"), which, while it emits a
warning that text() should be used here (note that the issue
does not impact cases where text() is used explicitly),
still produces a different query than previously where the “name desc”
expression is copied into the columns clause inappropriately. The
resolution is such that the “joined eager loading” aspect of the
feature will skip over these so-called “label reference” expressions
when augmenting the inner columns clause, as though they were
text() constructs already.
References: #3392
[orm] [bug] Fixed a regression regarding the MapperEvents.instrument_class()
event where its invocation was moved to be after the class manager’s
instrumentation of the class, which is the opposite of what the
documentation for the event explicitly states. The rationale for the
switch was due to Declarative taking the step of setting up
the full “instrumentation manager” for a class before it was mapped
for the purpose of the new @declared_attr features
described in Improvements to declarative mixins, @declared_attr and related features, but the change was also made
against the classical use of mapper() for consistency.
However, SQLSoup relies upon the instrumentation event happening
before any instrumentation under classical mapping.
The behavior is reverted in the case of classical and declarative
mapping, the latter implemented by using a simple memoization
without using class manager.¶
References: #3388
[orm] [bug] Fixed issue in new QueryEvents.before_compile() event where
changes made to the Query object’s collection of entities
to load within the event would render in the SQL, but would not
be reflected during the loading process.¶
References: #3387
[engine] [feature] New features added to support engine/pool plugins with advanced
functionality. Added a new “soft invalidate” feature to the
connection pool at the level of the checked out connection wrapper
as well as the _ConnectionRecord. This works similarly
to a modern pool invalidation in that connections aren’t actively
closed, but are recycled only on next checkout; this is essentially
a per-connection version of that feature. A new event
PoolEvents.soft_invalidate is added to complement it.
Also added new flag
ExceptionContext.invalidate_pool_on_disconnect.
Allows an error handler within ConnectionEvents.handle_error()
to maintain a “disconnect” condition, but to handle calling invalidate
on individual connections in a specific manner within the event.
References: #3379
[engine] [feature] Added new event DialectEvents.do_connect, which allows
interception / replacement of when the Dialect.connect()
hook is called to create a DBAPI connection. Also added
dialect plugin hooks Dialect.get_dialect_cls() and
Dialect.engine_created() which allow external plugins to
add events to existing dialects using entry points.¶
References: #3355
[sql] [feature] Added a placeholder method TypeEngine.compare_against_backend()
which is now consumed by Alembic migrations as of 0.7.6. User-defined
types can implement this method to assist in the comparison of
a type against one reflected from the database.¶
[sql] [bug] Fixed bug where the truncation of long labels in SQL could produce a label that overlapped another label that is not truncated; this because the length threshold for truncation was greater than the portion of the label that remains after truncation. These two values have now been made the same; label_length - 6. The effect here is that shorter column labels will be “truncated” where they would not have been truncated before.¶
References: #3396
[sql] [bug] Fixed regression due to #3282 where the tables collection
passed as a keyword argument to the DDLEvents.before_create(),
DDLEvents.after_create(), DDLEvents.before_drop(), and
DDLEvents.after_drop() events would no longer be a list
of tables, but instead a list of tuples which contained a second
entry with foreign keys to be added or dropped. As the tables
collection, while documented as not necessarily stable, has come
to be relied upon, this change is considered a regression.
Additionally, in some cases for “drop”, this collection would
be an iterator that would cause the operation to fail if
prematurely iterated. The collection is now a list of table
objects in all cases and test coverage for the format of this
collection is now added.¶
References: #3391
[sql] [bug] Fixed a regression that was incorrectly fixed in 1.0.0b4 (hence becoming two regressions); reports that SELECT statements would GROUP BY a label name and fail was misconstrued that certain backends such as SQL Server should not be emitting ORDER BY or GROUP BY on a simple label name at all; when in fact, we had forgotten that 0.9 was already emitting ORDER BY on a simple label name for all backends, as described in Label constructs can now render as their name alone in an ORDER BY, even though 1.0 includes a rewrite of this logic as part of #2992. As far as emitting GROUP BY against a simple label, even PostgreSQL has cases where it will raise an error even though the label to group on should be apparent, so it is clear that GROUP BY should never be rendered in this way automatically.
In 1.0.2, SQL Server, Firebird and others will again emit ORDER BY on
a simple label name when passed a
Label construct that is also present in the columns clause.
Additionally, no backend will emit GROUP BY against the simple label
name only when passed a Label construct.
[orm] [bug] Fixed issue where a query of the form
query(B).filter(B.a != A(id=7)) would render the NEVER_SET
symbol, when
given a transient object. For a persistent object, it would
always use the persisted database value and not the currently
set value. Assuming autoflush is turned on, this usually would
not be apparent for persistent values, as any pending changes
would be flushed first in any case. However, this is inconsistent
vs. the logic used for the non-negated comparison,
query(B).filter(B.a == A(id=7)), which does use the
current value and additionally allows comparisons to transient
objects. The comparison now uses the current value and not
the database-persisted value.
Unlike the other NEVER_SET issues that are repaired as regressions
caused by #3061 in this release, this particular issue is
present at least as far back as 0.8 and possibly earlier, however it
was discovered as a result of repairing the related NEVER_SET
issues.
References: #3374
[orm] [bug] Fixed unexpected use regression cause by #3061 where
the NEVER_SET
symbol could leak into relationship-oriented queries, including
filter() and with_parent() queries. The None symbol
is returned in all cases, however many of these queries have never
been correctly supported in any case, and produce comparisons
to NULL without using the IS operator. For this reason, a warning
is also added to that subset of relationship queries that don’t
currently provide for IS NULL.
References: #3371
[orm] [bug] Fixed a regression caused by #3061 where the NEVER_SET symbol could leak into a lazyload query, subsequent to the flush of a pending object. This would occur typically for a many-to-one relationship that does not use a simple “get” strategy. The good news is that the fix improves efficiency vs. 0.9, because we can now skip the SELECT statement entirely when we detect NEVER_SET symbols present in the parameters; prior to #3061, we couldn’t discern if the None here were set or not.¶
References: #3368
[engine] [bug] Added the string value "none" to those accepted by the
Pool.reset_on_return parameter as a synonym for None,
so that string values can be used for all settings, allowing
utilities like engine_from_config() to be usable without
issue.¶
This change is also backported to: 0.9.10
References: #3375
[sql] [bug] Fixed issue where a straight SELECT EXISTS query would fail to
assign the proper result type of Boolean to the result mapping, and
instead would leak column types from within the query into the
result map. This issue exists in 0.9 and earlier as well, however
has less of an impact in those versions. In 1.0, due to #918
this becomes a regression in that we now rely upon the result mapping
to be very accurate, else we can assign result-type processors to
the wrong column. In all versions, this issue also has the effect
that a simple EXISTS will not apply the Boolean type handler, leading
to simple 1/0 values for backends without native boolean instead of
True/False. The fix includes that an EXISTS columns argument
will be anon-labeled like other column expressions; a similar fix is
implemented for pure-boolean expressions like not_(True()).¶
References: #3372
[sqlite] [bug] Fixed a regression due to #3282, where due to the fact that we attempt to assume the availability of ALTER when creating/dropping schemas, in the case of SQLite we simply said to not worry about foreign keys at all, since ALTER is not available, when creating and dropping tables. This meant that the sorting of tables was basically skipped in the case of SQLite, and for the vast majority of SQLite use cases, this is not an issue.
However, users who were doing DROPs on SQLite with tables that contained data and with referential integrity turned on would then experience errors, as the dependency sorting does matter in the case of DROP with enforced constraints, when those tables have data (SQLite will still happily let you create foreign keys to nonexistent tables and drop tables referring to existing ones with constraints enabled, as long as there’s no data being referenced).
In order to maintain the new feature of #3282 while still
allowing a SQLite DROP operation to maintain ordering, we now
do the sort with full FKs taken under consideration, and if we encounter
an unresolvable cycle, only then do we forego attempting to sort
the tables; we instead emit a warning and go with the unsorted list.
If an environment needs both ordered DROPs and has foreign key
cycles, then the warning notes they will need to restore the
use_alter flag to their ForeignKey and
ForeignKeyConstraint objects so that just those objects will
be omitted from the dependency sort.
See also
The use_alter flag on ForeignKeyConstraint is (usually) no longer needed - contains an updated note about SQLite.
References: #3378
[firebird] [bug] Fixed a regression due to #3034 where limit/offset clauses were not properly interpreted by the Firebird dialect. Pull request courtesy effem-git.¶
References: #3380
[firebird] [bug] Fixed support for “literal_binds” mode when using limit/offset with Firebird, so that the values are again rendered inline when this is selected. Related to #3034.¶
References: #3381
[orm] [feature] Added new argument Query.update.update_args which allows
kw arguments such as mysql_limit to be passed to the underlying
Update construct. Pull request courtesy Amir Sadoughi.¶
[orm] [bug] Identified an inconsistency when handling Query.join() to the
same target more than once; it implicitly dedupes only in the case of
a relationship join, and due to #3233, in 1.0 a join
to the same table twice behaves differently than 0.9 in that it no
longer erroneously aliases. To help document this change,
the verbiage regarding #3233 in the migration notes has
been generalized, and a warning has been added when Query.join()
is called against the same target relationship more than once.¶
References: #3367
[orm] [bug] Made a small improvement to the heuristics of relationship when
determining remote side with semi-self-referential (e.g. two joined
inh subclasses referring to each other), non-simple join conditions
such that the parententity is taken into account and can reduce the
need for using the remote() annotation; this can restore some
cases that might have worked without the annotation prior to 0.9.4
via #2948.¶
References: #3364
[sql] [feature] The topological sorting used to sort Table objects
and available via the MetaData.sorted_tables collection
will now produce a deterministic ordering; that is, the same
ordering each time given a set of tables with particular names
and dependencies. This is to help with comparison of DDL scripts
and other use cases. The tables are sent to the topological sort
sorted by name, and the topological sort itself will process
the incoming data in an ordered fashion. Pull request
courtesy Sebastian Bank.
References: #3084
[sql] [bug] Fixed issue where a MetaData object that used a naming
convention would not properly work with pickle. The attribute was
skipped leading to inconsistencies and failures if the unpickled
MetaData object were used to base additional tables
from.¶
This change is also backported to: 0.9.10
References: #3362
[postgresql] [bug] Fixed a long-standing bug where the Enum type as used
with the psycopg2 dialect in conjunction with non-ascii values
and native_enum=False would fail to decode return results properly.
This stemmed from when the PG postgresql.ENUM type used
to be a standalone type without a “non native” option.¶
This change is also backported to: 0.9.10
References: #3354
[mssql] [bug] Fixed a regression where the “last inserted id” mechanics would fail to store the correct value for MSSQL on an INSERT where the primary key value was present in the insert params before execution, as well as in the case where an INSERT from SELECT would state the target columns as column objects, instead of string keys.¶
References: #3360
[mssql] [bug] Using the Binary constructor now present in pymssql rather than
patching one in. Pull request courtesy Ramiro Morales.¶
[bug] [tests] Fixed the pathing used when tests run; for sqla_nose.py and py.test, the “./lib” prefix is again inserted at the head of sys.path but only if sys.flags.no_user_site isn’t set; this makes it act just like the way Python puts “.” in the current path by default. For tox, we are setting the PYTHONNOUSERSITE flag now.¶
References: #3356
[orm] [bug] Fixed bug where the state tracking within multiple, nested
Session.begin_nested() operations would fail to propagate
the “dirty” flag for an object that had been updated within
the inner savepoint, such that if the enclosing savepoint were
rolled back, the object would not be part of the state that was
expired and therefore reverted to its database state.¶
This change is also backported to: 0.9.10
References: #3352
[orm] [bug] Query doesn’t support joins, subselects, or special
FROM clauses when using the Query.update() or
Query.delete() methods; instead of silently ignoring these
fields if methods like Query.join() or
Query.select_from() has been called, an error is raised.
In 0.9.10 this only emits a warning.¶
References: #3349
[orm] [bug] Added a list() call around a weak dictionary used within the commit phase of the session, which without it could cause a “dictionary changed size during iter” error if garbage collection interacted within the process. Change was introduced by #3139.¶
[orm] [bug] Fixed a bug related to “nested” inner join eager loading, which exists in 0.9 as well but is more of a regression in 1.0 due to #3008 which turns on “nested” by default, such that a joined eager load that travels across sibling paths from a common ancestor using innerjoin=True will correctly splice each “innerjoin” sibling into the appropriate part of the join, when a series of inner/outer joins are mixed together.¶
References: #3347
[sql] [bug] The warning emitted by the unicode type for a non-unicode type has been liberalized to warn for values that aren’t even string values, such as integers; previously, the updated warning system of 1.0 made use of string formatting operations which would raise an internal TypeError. While these cases should ideally raise totally, some backends like SQLite and MySQL do accept them and are potentially in use by legacy code, not to mention that they will always pass through if unicode conversion is turned off for the target backend.¶
References: #3346
[sql] [bug] Fixed bug in new “label resolution” feature of #2992 where
a label that was anonymous, then labeled again with a name, would
fail to be locatable via a textual label. This situation occurs
naturally when a mapped column_property() is given an
explicit label in a query.¶
References: #3340
[sql] [bug] Fixed bug in new “label resolution” feature of #2992 where the string label placed in the order_by() or group_by() of a statement would place higher priority on the name as found inside the FROM clause instead of a more locally available name inside the columns clause.¶
References: #3335
[schema] [feature] The “auto-attach” feature of constraints such as UniqueConstraint
and CheckConstraint has been further enhanced such that
when the constraint is associated with non-table-bound Column
objects, the constraint will set up event listeners with the
columns themselves such that the constraint auto attaches at the
same time the columns are associated with the table. This in particular
helps in some edge cases in declarative but is also of general use.
References: #3341
[mysql] [bug] [pymysql] Fixed unicode support for PyMySQL when using an “executemany” operation with unicode parameters. SQLAlchemy now passes both the statement as well as the bound parameters as unicode objects, as PyMySQL generally uses string interpolation internally to produce the final statement, and in the case of executemany does the “encode” step only on the final statement.¶
This change is also backported to: 0.9.10
References: #3337
[mssql] [bug] [firebird] [oracle] [sybase] Turned off the “simple order by” flag on the MSSQL, Oracle dialects; this is the flag that per #2992 causes an order by or group by an expression that’s also in the columns clause to be copied by label, even if referenced as the expression object. The behavior for MSSQL is now the old behavior that copies the whole expression in by default, as MSSQL can be picky on these particularly in GROUP BY expressions. The flag is also turned off defensively for the Firebird and Sybase dialects.
Note
this resolution was incorrect, please see version 1.0.2 for a rework of this resolution.
References: #3338
[orm] [bug] Fixed unexpected use regression from pullreq github:137 where
Py2K unicode literals (e.g. u"") would not be accepted by the
relationship.cascade option.
Pull request courtesy Julien Castets.¶
References: #3327
[change] [declarative] [orm] Loosened some restrictions that were added to @declared_attr
objects, such that they were prevented from being called outside
of the declarative process; this is related to the enhancements
of #3150 which allow @declared_attr to return a value that is
cached based on the current class as it’s being configured.
The exception raise has been removed, and the behavior changed
so that outside of the declarative process, the function decorated by
@declared_attr is called every time just like a regular
@property, without using any caching, as none is available
at this stage.¶
References: #3331
[engine] [bug] The “auto close” for ResultProxy is now a “soft” close.
That is, after exhausting all rows using the fetch methods, the
DBAPI cursor is released as before and the object may be safely
discarded, but the fetch methods may continue to be called for which
they will return an end-of-result object (None for fetchone, empty list
for fetchmany and fetchall). Only if ResultProxy.close()
is called explicitly will these methods raise the “result is closed”
error.
[mysql] [bug] [py3k] Fixed the mysql.BIT type on Py3K which was not using the
ord() function correctly. Pull request courtesy David Marin.¶
This change is also backported to: 0.9.10
References: #3333
[mysql] [bug] Fixes to fully support using the 'utf8mb4' MySQL-specific charset
with MySQL dialects, in particular MySQL-Python and PyMySQL. In
addition, MySQL databases that report more unusual charsets such as
‘koi8u’ or ‘eucjpms’ will also work correctly. Pull request
courtesy Thomas Grainger.¶
References: #2771
Version 1.0.0b1 is the first release of the 1.0 series. Many changes described here are also present in the 0.9 and sometimes the 0.8 series as well. For changes that are specific to 1.0 with an emphasis on compatibility concerns, see What’s New in SQLAlchemy 1.0?.
[general] [feature] Structural memory use has been improved via much more significant use
of __slots__ for many internal objects. This optimization is
particularly geared towards the base memory size of large applications
that have lots of tables and columns, and greatly reduces memory
size for a variety of high-volume objects including event listening
internals, comparator objects and parts of the ORM attribute and
loader strategy system.
[general] [bug] The __module__ attribute is now set for all those SQL and
ORM functions that are derived as “public factory” symbols, which
should assist with documentation tools being able to report on the
target module.¶
References: #3218
[orm] [feature] Added a new entry "entity" to the dictionaries returned by
Query.column_descriptions. This refers to the primary ORM
mapped class or aliased class that is referred to by the expression.
Compared to the existing entry for "type", it will always be
a mapped entity, even if extracted from a column expression, or
None if the given expression is a pure core expression.
See also #3403 which repaired a regression in this feature
which was unreleased in 0.9.10 but was released in the 1.0 version.¶
This change is also backported to: 0.9.10
References: #3320
[orm] [feature] Added new parameter Session.connection.execution_options
which may be used to set up execution options on a Connection
when it is first checked out, before the transaction has begun.
This is used to set up options such as isolation level on the
connection before the transaction starts.
See also
Setting Transaction Isolation Levels - new documentation section detailing best practices for setting transaction isolation with sessions.
This change is also backported to: 0.9.9
References: #3296
[orm] [feature] Added new method Session.invalidate(), functions similarly
to Session.close(), except also calls
Connection.invalidate()
on all connections, guaranteeing that they will not be returned to
the connection pool. This is useful in situations e.g. dealing
with gevent timeouts when it is not safe to use the connection further,
even for rollbacks.¶
This change is also backported to: 0.9.9
[orm] [feature] The “primaryjoin” model has been stretched a bit further to allow
a join condition that is strictly from a single column to itself,
translated through some kind of SQL function or expression. This
is kind of experimental, but the first proof of concept is a
“materialized path” join condition where a path string is compared
to itself using “like”. The ColumnOperators.like() operator has
also been added to the list of valid operators to use in a primaryjoin
condition.¶
This change is also backported to: 0.9.5
References: #3029
[orm] [feature] Added new utility function make_transient_to_detached() which can
be used to manufacture objects that behave as though they were loaded
from a session, then detached. Attributes that aren’t present
are marked as expired, and the object can be added to a Session
where it will act like a persistent one.¶
This change is also backported to: 0.9.5
References: #3017
[orm] [feature] Added a new event suite QueryEvents. The
QueryEvents.before_compile() event allows the creation
of functions which may place additional modifications to
Query objects before the construction of the SELECT
statement. It is hoped that this event be made much more
useful via the advent of a new inspection system that will
allow for detailed modifications to be made against
Query objects in an automated fashion.
See also
References: #3317
[orm] [feature] The subquery wrapping which occurs when joined eager loading
is used with a one-to-many query that also features LIMIT,
OFFSET, or DISTINCT has been disabled in the case of a one-to-one
relationship, that is a one-to-many with
relationship.uselist set to False. This will produce
more efficient queries in these cases.
References: #3249
[orm] [feature] Mapped state internals have been reworked to allow for a 50% reduction
in callcounts specific to the “expiration” of objects, as in
the “auto expire” feature of Session.commit() and
for Session.expire_all(), as well as in the “cleanup” step
which occurs when object states are garbage collected.¶
References: #3307
[orm] [feature] A warning is emitted when the same polymorphic identity is assigned to two different mappers in the same hierarchy. This is typically a user error and means that the two different mapping types cannot be correctly distinguished at load time. Pull request courtesy Sebastian Bank.¶
References: #3262
[orm] [feature] A new series of Session methods which provide hooks
directly into the unit of work’s facility for emitting INSERT
and UPDATE statements has been created. When used correctly,
this expert-oriented system can allow ORM-mappings to be used
to generate bulk insert and update statements batched into
executemany groups, allowing the statements to proceed at
speeds that rival direct use of the Core.
See also
References: #3100
[orm] [feature] Added a parameter Query.join.isouter which is synonymous
with calling Query.outerjoin(); this flag is to provide a more
consistent interface compared to Core FromClause.join().
Pull request courtesy Jonathan Vanasco.¶
References: #3217
[orm] [feature] Added new event handlers AttributeEvents.init_collection()
and AttributeEvents.dispose_collection(), which track when
a collection is first associated with an instance and when it is
replaced. These handlers supersede the collection.linker()
annotation. The old hook remains supported through an event adapter.¶
[orm] [feature] The Query will raise an exception when Query.yield_per()
is used with mappings or options where either
subquery eager loading, or joined eager loading with collections,
would take place. These loading strategies are
not currently compatible with yield_per, so by raising this error,
the method is safer to use. Eager loads can be disabled with
the lazyload('*') option or Query.enable_eagerloads().
[orm] [feature] A new implementation for KeyedTuple used by the
Query object offers dramatic speed improvements when
fetching large numbers of column-oriented rows.
References: #3176
[orm] [feature] The behavior of joinedload.innerjoin as well as
relationship.innerjoin is now to use “nested”
inner joins, that is, right-nested, as the default behavior when an
inner join joined eager load is chained to an outer join eager load.
References: #3008
[orm] [feature] UPDATE statements can now be batched within an ORM flush into more performant executemany() call, similarly to how INSERT statements can be batched; this will be invoked within flush to the degree that subsequent UPDATE statements for the same mapping and table involve the identical columns within the VALUES clause, that no SET-level SQL expressions are embedded, and that the versioning requirements for the mapping are compatible with the backend dialect’s ability to return a correct rowcount for an executemany operation.¶
[orm] [feature] The info parameter has been added to the constructor for
SynonymProperty and ComparableProperty.¶
References: #2963
[orm] [feature] The InspectionAttr.info collection is now moved down to
InspectionAttr, where in addition to being available
on all MapperProperty objects, it is also now available
on hybrid properties, association proxies, when accessed via
Mapper.all_orm_descriptors.¶
References: #2971
[orm] [changed] The proc() callable passed to the create_row_processor()
method of custom Bundle classes now accepts only a single
“row” argument.
[orm] [changed] Deprecated event hooks removed: populate_instance,
create_instance, translate_row, append_result
See also
[orm] [bug] Fixed bug in subquery eager loading where a long chain of
eager loads across a polymorphic-subclass boundary in conjunction
with polymorphic loading would fail to locate the subclass-link in the
chain, erroring out with a missing property name on an
AliasedClass.¶
This change is also backported to: 0.9.5, 0.8.7
References: #3055
[orm] [bug] Fixed ORM bug where the class_mapper() function would mask
AttributeErrors or KeyErrors that should raise during mapper
configuration due to user errors. The catch for attribute/keyerror
has been made more specific to not include the configuration step.¶
This change is also backported to: 0.9.5, 0.8.7
References: #3047
[orm] [bug] Fixed bugs in ORM object comparisons where comparison of
many-to-one != None would fail if the source were an aliased
class, or if the query needed to apply special aliasing to the
expression due to aliased joins or polymorphic querying; also fixed
bug in the case where comparing a many-to-one to an object state
would fail if the query needed to apply special aliasing
due to aliased joins or polymorphic querying.¶
This change is also backported to: 0.9.9
References: #3310
[orm] [bug] Fixed bug where internal assertion would fail in the case where
an after_rollback() handler for a Session incorrectly
adds state to that Session within the handler, and the task
to warn and remove this state (established by #2389) attempts
to proceed.¶
This change is also backported to: 0.9.9
References: #3309
[orm] [bug] Fixed bug where TypeError raised when Query.join() called
with unknown kw arguments would raise its own TypeError due
to broken formatting. Pull request courtesy Malthe Borch.¶
This change is also backported to: 0.9.9
[orm] [bug] Fixed bug in lazy loading SQL construction whereby a complex primaryjoin that referred to the same “local” column multiple times in the “column that points to itself” style of self-referential join would not be substituted in all cases. The logic to determine substitutions here has been reworked to be more open-ended.¶
This change is also backported to: 0.9.9
References: #3300
[orm] [bug] The “wildcard” loader options, in particular the one set up by
the orm.load_only() option to cover all attributes not
explicitly mentioned, now takes into account the superclasses
of a given entity, if that entity is mapped with inheritance mapping,
so that attribute names within the superclasses are also omitted
from the load. Additionally, the polymorphic discriminator column
is unconditionally included in the list, just in the same way that
primary key columns are, so that even with load_only() set up,
polymorphic loading of subtypes continues to function correctly.¶
This change is also backported to: 0.9.9
References: #3287
[orm] [bug] [pypy] Fixed bug where if an exception were thrown at the start of a
Query before it fetched results, particularly when
row processors can’t be formed, the cursor would stay open with
results pending and not actually be closed. This is typically only
an issue on an interpreter like PyPy where the cursor isn’t
immediately GC’ed, and can in some circumstances lead to transactions/
locks being open longer than is desirable.¶
This change is also backported to: 0.9.9
References: #3285
[orm] [bug] Fixed a leak which would occur in the unsupported and highly non-recommended use case of replacing a relationship on a fixed mapped class many times, referring to an arbitrarily growing number of target mappers. A warning is emitted when the old relationship is replaced, however if the mapping were already used for querying, the old relationship would still be referenced within some registries.¶
This change is also backported to: 0.9.9
References: #3251
[orm] [bug] [sqlite] Fixed bug regarding expression mutations which could express
itself as a “Could not locate column” error when using
Query to select from multiple, anonymous column
entities when querying against SQLite, as a side effect of the
“join rewriting” feature used by the SQLite dialect.¶
This change is also backported to: 0.9.9
References: #3241
[orm] [bug] Fixed bug where the ON clause for Query.join(),
and Query.outerjoin() to a single-inheritance subclass
using of_type() would not render the “single table criteria” in
the ON clause if the from_joinpoint=True flag were set.¶
This change is also backported to: 0.9.9
References: #3232
[orm] [bug] [engine] Fixed bug that affected generally the same classes of event
as that of #3199, when the named=True parameter
would be used. Some events would fail to register, and others
would not invoke the event arguments correctly, generally in the
case of when an event was “wrapped” for adaption in some other way.
The “named” mechanics have been rearranged to not interfere with
the argument signature expected by internal wrapper functions.¶
This change is also backported to: 0.9.8
References: #3197
[orm] [bug] Fixed bug that affected many classes of event, particularly
ORM events but also engine events, where the usual logic of
“de duplicating” a redundant call to event.listen()
with the same arguments would fail, for those events where the
listener function is wrapped. An assertion would be hit within
registry.py. This assertion has now been integrated into the
deduplication check, with the added bonus of a simpler means
of checking deduplication across the board.¶
This change is also backported to: 0.9.8
References: #3199
[orm] [bug] Fixed warning that would emit when a complex self-referential primaryjoin contained functions, while at the same time remote_side was specified; the warning would suggest setting “remote side”. It now only emits if remote_side isn’t present.¶
This change is also backported to: 0.9.8
References: #3194
[orm] [bug] [eagerloading] Fixed a regression caused by #2976 released in 0.9.4 where the “outer join” propagation along a chain of joined eager loads would incorrectly convert an “inner join” along a sibling join path into an outer join as well, when only descendant paths should be receiving the “outer join” propagation; additionally, fixed related issue where “nested” join propagation would take place inappropriately between two sibling join paths.¶
This change is also backported to: 0.9.7
References: #3131
[orm] [bug] Fixed a regression from 0.9.0 due to #2736 where the
Query.select_from() method no longer set up the “from
entity” of the Query object correctly, so that
subsequent Query.filter_by() or Query.join()
calls would fail to check the appropriate “from” entity when
searching for attributes by string name.¶
This change is also backported to: 0.9.7
[orm] [bug] Fixed bug where items that were persisted, deleted, or had a primary key change within a savepoint block would not participate in being restored to their former state (not in session, in session, previous PK) after the outer transaction were rolled back.¶
This change is also backported to: 0.9.7
References: #3108
[orm] [bug] Fixed bug in subquery eager loading in conjunction with
with_polymorphic(), the targeting of entities and columns
in the subquery load has been made more accurate with respect
to this type of entity and others.¶
This change is also backported to: 0.9.7
References: #3106
[orm] [bug] Additional checks have been added for the case where an inheriting mapper is implicitly combining one of its column-based attributes with that of the parent, where those columns normally don’t necessarily share the same value. This is an extension of an existing check that was added via #1892; however this new check emits only a warning, instead of an exception, to allow for applications that may be relying upon the existing behavior.
¶This change is also backported to: 0.9.5
References: #3042
[orm] [bug] Modified the behavior of orm.load_only() such that primary key
columns are always added to the list of columns to be “undeferred”;
otherwise, the ORM can’t load the row’s identity. Apparently,
one can defer the mapped primary keys and the ORM will fail, that
hasn’t been changed. But as load_only is essentially saying
“defer all but X”, it’s more critical that PK cols not be part of this
deferral.¶
This change is also backported to: 0.9.5
References: #3080
[orm] [bug] Fixed a few edge cases which arise in the so-called “row switch” scenario, where an INSERT/DELETE can be turned into an UPDATE. In this situation, a many-to-one relationship set to None, or in some cases a scalar attribute set to None, may not be detected as a net change in value, and therefore the UPDATE would not reset what was on the previous row. This is due to some as-yet unresolved side effects of the way attribute history works in terms of implicitly assuming None isn’t really a “change” for a previously un-set attribute. See also #3061.
Note
This change has been REVERTED in 0.9.6. The full fix will be in version 1.0 of SQLAlchemy.
This change is also backported to: 0.9.5
References: #3060
[orm] [bug] Related to #3060, an adjustment has been made to the unit of work such that loading for related many-to-one objects is slightly more aggressive, in the case of a graph of self-referential objects that are to be deleted; the load of related objects is to help determine the correct order for deletion if passive_deletes is not set.¶
This change is also backported to: 0.9.5
[orm] [bug] Fixed bug in SQLite join rewriting where anonymized column names due to repeats would not correctly be rewritten in subqueries. This would affect SELECT queries with any kind of subquery + join.¶
This change is also backported to: 0.9.5
References: #3057
[orm] [bug] [sql] Fixes to the newly enhanced boolean coercion in #2804 where
the new rules for “where” and “having” woudn’t take effect for the
“whereclause” and “having” kw arguments of the select() construct,
which is also what Query uses so wasn’t working in the
ORM either.¶
This change is also backported to: 0.9.5
References: #3013
[orm] [bug] Fixed bug where the session attachment error “object is already attached to session X” would fail to prevent the object from also being attached to the new session, in the case that execution continued after the error raise occurred.¶
References: #3301
[orm] [bug] The primary Mapper of a Query is now passed to the
Session.get_bind() method when calling upon
Query.count(), Query.update(), Query.delete(),
as well as queries against mapped columns,
column_property objects, and SQL functions and expressions
derived from mapped columns. This allows sessions that rely upon
either customized Session.get_bind() schemes or “bound” metadata
to work in all relevant cases.
[orm] [bug] The PropComparator.of_type() modifier has been
improved in conjunction with loader directives such as
joinedload() and contains_eager() such that if
two PropComparator.of_type() modifiers of the same
base type/path are encountered, they will be joined together
into a single “polymorphic” entity, rather than replacing
the entity of type A with the one of type B. E.g.
a joinedload of A.b.of_type(BSub1)->BSub1.c combined with
joinedload of A.b.of_type(BSub2)->BSub2.c will create a
single joinedload of A.b.of_type((BSub1, BSub2)) -> BSub1.c, BSub2.c,
without the need for the with_polymorphic to be explicit
in the query.
See also
Eager Loading of Specific or Polymorphic Subtypes - contains an updated example illustrating the new format.
References: #3256
[orm] [bug] Repaired support of the copy.deepcopy() call when used by the
orm.util.CascadeOptions argument, which occurs
if copy.deepcopy() is being used with relationship()
(not an officially supported use case). Pull request courtesy
duesenfranz.¶
[orm] [bug] Fixed bug where Session.expunge() would not fully detach
the given object if the object had been subject to a delete
operation that was flushed, but not committed. This would also
affect related operations like make_transient().
References: #3139
[orm] [bug] A warning is emitted in the case of multiple relationships that ultimately will populate a foreign key column in conflict with another, where the relationships are attempting to copy values from different source columns. This occurs in the case where composite foreign keys with overlapping columns are mapped to relationships that each refer to a different referenced column. A new documentation section illustrates the example as well as how to overcome the issue by specifying “foreign” columns specifically on a per-relationship basis.
See also
References: #3230
[orm] [bug] The Query.update() method will now convert string key
names in the given dictionary of values into mapped attribute names
against the mapped class being updated. Previously, string names
were taken in directly and passed to the core update statement without
any means to resolve against the mapped entity. Support for synonyms
and hybrid attributes as the subject attributes of
Query.update() are also supported.
References: #3228
[orm] [bug] Improvements to the mechanism used by Session to locate
“binds” (e.g. engines to use), such engines can be associated with
mixin classes, concrete subclasses, as well as a wider variety
of table metadata such as joined inheritance tables.
References: #3035
[orm] [bug] Fixed bug in single table inheritance where a chain of joins that included the same single inh entity more than once (normally this should raise an error) could, in some cases depending on what was being joined “from”, implicitly alias the second case of the single inh entity, producing a query that “worked”. But as this implicit aliasing is not intended in the case of single table inheritance, it didn’t really “work” fully and was very misleading, since it wouldn’t always appear.
¶References: #3233
[orm] [bug] The ON clause rendered when using Query.join(),
Query.outerjoin(), or the standalone orm.join() /
orm.outerjoin() functions to a single-inheritance subclass will
now include the “single table criteria” in the ON clause even
if the ON clause is otherwise hand-rolled; it is now added to the
criteria using AND, the same way as if joining to a single-table
target using relationship or similar.
This is sort of in-between feature and bug.
¶References: #3222
[orm] [bug] A major rework to the behavior of expression labels, most
specifically when used with ColumnProperty constructs with
custom SQL expressions and in conjunction with the “order by
labels” logic first introduced in 0.9. Fixes include that an
order_by(Entity.some_col_prop) will now make use of “order by
label” rules even if Entity has been subject to aliasing,
either via inheritance rendering or via the use of the
aliased() construct; rendering of the same column property
multiple times with aliasing (e.g. query(Entity.some_prop,
entity_alias.some_prop)) will label each occurrence of the
entity with a distinct label, and additionally “order by
label” rules will work for both (e.g.
order_by(Entity.some_prop, entity_alias.some_prop)).
Additional issues that could prevent the “order by label”
logic from working in 0.9, most notably that the state of a
Label could change such that “order by label” would stop
working depending on how things were called, has been fixed.
[orm] [bug] Changed the approach by which the “single inheritance criterion”
is applied, when using Query.from_self(), or its common
user Query.count(). The criteria to limit rows to those
with a certain type is now indicated on the inside subquery,
not the outside one, so that even if the “type” column is not
available in the columns clause, we can filter on it on the “inner”
query.
References: #3177
[orm] [bug] Made a small adjustment to the mechanics of lazy loading, such that it has less chance of interfering with a joinload() in the very rare circumstance that an object points to itself; in this scenario, the object refers to itself while loading its attributes which can cause a mixup between loaders. The use case of “object points to itself” is not fully supported, but the fix also removes some overhead so for now is part of testing.¶
References: #3145
[orm] [bug] The “resurrect” ORM event has been removed. This event hook had no purpose since the old “mutable attribute” system was removed in 0.8.¶
References: #3171
[orm] [bug] Fixed bug where attribute “set” events or columns with
@validates would have events triggered within the flush process,
when those columns were the targets of a “fetch and populate”
operation, such as an autoincremented primary key, a Python side
default, or a server-side default “eagerly” fetched via RETURNING.¶
References: #3167
[orm] [bug] [py3k] The IdentityMap exposed from Session.identity_map
now returns lists for items() and values() in Py3K.
Early porting to Py3K here had these returning iterators, when
they technically should be “iterable views”..for now, lists are OK.¶
[orm] [bug] The “evaluator” for query.update()/delete() won’t work with multi-table updates, and needs to be set to synchronize_session=False or synchronize_session=’fetch’; this now raises an exception, with a message to change the synchronize setting. This is upgraded from a warning emitted as of 0.9.7.¶
References: #3117
[orm] [change] Mapped attributes marked as deferred without explicit undeferral
will now remain “deferred” even if their column is otherwise
present in the result set in some way. This is a performance
enhancement in that an ORM load no longer spends time searching
for each deferred column when the result set is obtained. However,
for an application that has been relying upon this, an explicit
undefer() or similar option should now be used.¶
[orm] [enhancement] Adjustment to attribute mechanics concerning when a value is implicitly initialized to None via first access; this action, which has always resulted in a population of the attribute, no longer does so; the None value is returned but the underlying attribute receives no set event. This is consistent with how collections work and allows attribute mechanics to behave more consistently; in particular, getting an attribute with no value does not squash the event that should proceed if the value is actually set to None.
where bound parameters are rendered inline as strings based on a compile-time option. Work on this feature is courtesy of Dobes Vandermeer.
¶
References: #3061
[feature] [declarative] [orm] The declared_attr construct has newly improved
behaviors and features in conjunction with declarative. The
decorated function will now have access to the final column
copies present on the local mixin when invoked, and will also
be invoked exactly once for each mapped class, the returned result
being memoized. A new modifier declared_attr.cascading
is added as well.
References: #3150
[bug] [declarative] [orm] Fixed “‘NoneType’ object has no attribute ‘concrete’” error
when using AbstractConcreteBase in conjunction with
a subclass that declares __abstract__.¶
This change is also backported to: 0.9.8
References: #3185
[bug] [declarative] [orm] Fixed bug where using an __abstract__ mixin in the middle
of a declarative inheritance hierarchy would prevent attributes
and configuration being correctly propagated from the base class
to the inheriting class.¶
[bug] [declarative] [orm] A relationship set up with declared_attr on
a AbstractConcreteBase base class will now be configured
on the abstract base mapping automatically, in addition to being
set up on descendant concrete classes as usual.
References: #2670
[engine] [feature] Added new user-space accessors for viewing transaction isolation
levels; Connection.get_isolation_level(),
Connection.default_isolation_level.¶
This change is also backported to: 0.9.9
[engine] [feature] Added new event ConnectionEvents.handle_error(), a more
fully featured and comprehensive replacement for
ConnectionEvents.dbapi_error().¶
This change is also backported to: 0.9.7
References: #3076
[engine] [feature] A new style of warning can be emitted which will “filter” up to N occurrences of a parameterized string. This allows parameterized warnings that can refer to their arguments to be delivered a fixed number of times until allowing Python warning filters to squelch them, and prevents memory from growing unbounded within Python’s warning registries.
¶References: #3178
[engine] [bug] Fixed bug in Connection and pool where the
Connection.invalidate() method, or an invalidation due
to a database disconnect, would fail if the
isolation_level parameter had been used with
Connection.execution_options(); the “finalizer” that resets
the isolation level would be called on the no longer opened connection.¶
This change is also backported to: 0.9.9
References: #3302
[engine] [bug] A warning is emitted if the isolation_level parameter is used
with Connection.execution_options() when a Transaction
is in play; DBAPIs and/or SQLAlchemy dialects such as psycopg2,
MySQLdb may implicitly rollback or commit the transaction, or
not change the setting til next transaction, so this is never safe.¶
This change is also backported to: 0.9.9
References: #3296
[engine] [bug] The execution options passed to an Engine either via
create_engine.execution_options or
Engine.update_execution_options() are not passed to the
special Connection used to initialize the dialect
within the “first connect” event; dialects will usually
perform their own queries in this phase, and none of the
current available options should be applied here. In
particular, the “autocommit” option was causing an attempt to
autocommit within this initial connect which would fail with
an AttributeError due to the non-standard state of the
Connection.¶
This change is also backported to: 0.9.8
References: #3200
[engine] [bug] The string keys that are used to determine the columns impacted for an INSERT or UPDATE are now sorted when they contribute towards the “compiled cache” cache key. These keys were previously not deterministically ordered, meaning the same statement could be cached multiple times on equivalent keys, costing both in terms of memory as well as performance.¶
This change is also backported to: 0.9.8
References: #3165
[engine] [bug] Fixed bug which would occur if a DBAPI exception occurs when the engine first connects and does its initial checks, and the exception is not a disconnect exception, yet the cursor raises an error when we try to close it. In this case the real exception would be quashed as we tried to log the cursor close exception via the connection pool and failed, as we were trying to access the pool’s logger in a way that is inappropriate in this very specific scenario.¶
This change is also backported to: 0.9.5
References: #3063
[engine] [bug] Fixed some “double invalidate” situations were detected where a connection invalidation could occur within an already critical section like a connection.close(); ultimately, these conditions are caused by the change in #2907, in that the “reset on return” feature calls out to the Connection/Transaction in order to handle it, where “disconnect detection” might be caught. However, it’s possible that the more recent change in #2985 made it more likely for this to be seen as the “connection invalidate” operation is much quicker, as the issue is more reproducible on 0.9.4 than 0.9.3.
Checks are now added within any section that an invalidate might occur to halt further disallowed operations on the invalidated connection. This includes two fixes both at the engine level and at the pool level. While the issue was observed with highly concurrent gevent cases, it could in theory occur in any kind of scenario where a disconnect occurs within the connection close operation.
¶This change is also backported to: 0.9.5
References: #3043
[engine] [bug] The engine-level error handling and wrapping routines will now
take effect in all engine connection use cases, including
when user-custom connect routines are used via the
create_engine.creator parameter, as well as when
the Connection encounters a connection error on
revalidation.
References: #3266
[engine] [bug] Removing (or adding) an event listener at the same time that the event
is being run itself, either from inside the listener or from a
concurrent thread, now raises a RuntimeError, as the collection used is
now an instance of colletions.deque() and does not support changes
while being iterated. Previously, a plain Python list was used where
removal from inside the event itself would produce silent failures.¶
References: #3163
[sql] [feature] Liberalized the contract for Index a bit in that you can
specify a text() expression as the target; the index no longer
needs to have a table-bound column present if the index is to be
manually added to the table, either via inline declaration or via
Table.append_constraint().¶
This change is also backported to: 0.9.5
References: #3028
[sql] [feature] Added new flag expression.between.symmetric, when set to True
renders “BETWEEN SYMMETRIC”. Also added a new negation operator
“notbetween_op”, which now allows an expression like ~col.between(x, y)
to render as “col NOT BETWEEN x AND y”, rather than a parenthesized NOT
string.¶
This change is also backported to: 0.9.5
References: #2990
[sql] [feature] The SQL compiler now generates the mapping of expected columns such that they are matched to the received result set positionally, rather than by name. Originally, this was seen as a way to handle cases where we had columns returned with difficult-to-predict names, though in modern use that issue has been overcome by anonymous labeling. In this version, the approach basically reduces function call count per-result by a few dozen calls, or more for larger sets of result columns. The approach still degrades into a modern version of the old approach if any discrepancy in size exists between the compiled set of columns versus what was received, so there’s no issue for partially or fully textual compilation scenarios where these lists might not line up.¶
References: #918
[sql] [feature] Literal values within a DefaultClause, which is invoked
when using the Column.server_default parameter, will
now be rendered using the “inline” compiler, so that they are rendered
as-is, rather than as bound parameters.
References: #3087
[sql] [feature] The type of expression is reported when an object passed to a SQL expression unit can’t be interpreted as a SQL fragment; pull request courtesy Ryan P. Kelly.¶
[sql] [feature] Added a new parameter Table.tometadata.name to
the Table.tometadata() method. Similar to
Table.tometadata.schema, this argument causes the newly
copied Table to take on the new name instead of
the existing one. An interesting capability this adds is that of
copying a Table object to the same MetaData
target with a new name. Pull request courtesy n.d. parker.¶
[sql] [feature] Exception messages have been spiffed up a bit. The SQL statement and parameters are not displayed if None, reducing confusion for error messages that weren’t related to a statement. The full module and classname for the DBAPI-level exception is displayed, making it clear that this is a wrapped DBAPI exception. The statement and parameters themselves are bounded within a bracketed sections to better isolate them from the error message and from each other.¶
References: #3172
[sql] [feature] Insert.from_select() now includes Python and SQL-expression
defaults if otherwise unspecified; the limitation where non-
server column defaults aren’t included in an INSERT FROM
SELECT is now lifted and these expressions are rendered as
constants into the SELECT statement.
[sql] [feature] The UniqueConstraint construct is now included when
reflecting a Table object, for databases where this
is applicable. In order to achieve this
with sufficient accuracy, MySQL and PostgreSQL now contain features
that correct for the duplication of indexes and unique constraints
when reflecting tables, indexes, and constraints.
In the case of MySQL, there is not actually a “unique constraint”
concept independent of a “unique index”, so for this backend
UniqueConstraint continues to remain non-present for a
reflected Table. For PostgreSQL, the query used to
detect indexes against pg_index has been improved to check for
the same construct in pg_constraint, and the implicitly
constructed unique index is not included with a
reflected Table.
In both cases, the Inspector.get_indexes() and the
Inspector.get_unique_constraints() methods return both
constructs individually, but include a new token
duplicates_constraint in the case of PostgreSQL or
duplicates_index in the case
of MySQL to indicate when this condition is detected.
Pull request courtesy Johannes Erdfelt.
References: #3184
[sql] [feature] Added new method Select.with_statement_hint() and ORM
method Query.with_statement_hint() to support statement-level
hints that are not specific to a table.¶
References: #3206
[sql] [feature] The info parameter has been added as a constructor argument
to all schema constructs including MetaData,
Index, ForeignKey, ForeignKeyConstraint,
UniqueConstraint, PrimaryKeyConstraint,
CheckConstraint.¶
References: #2963
[sql] [feature] The Table.autoload_with flag now implies that
Table.autoload should be True. Pull request
courtesy Malik Diarra.¶
References: #3027
[sql] [feature] The Select.limit() and Select.offset() methods
now accept any SQL expression, in addition to integer values, as
arguments. Typically this is used to allow a bound parameter to be
passed, which can be substituted with a value later thus allowing
Python-side caching of the SQL query. The implementation
here is fully backwards compatible with existing third party dialects,
however those dialects which implement special LIMIT/OFFSET systems
will need modification in order to take advantage of the new
capabilities. Limit and offset also support “literal_binds” mode,¶
References: #3034
[sql] [changed] The column() and table()
constructs are now importable from the “from sqlalchemy” namespace,
just like every other Core construct.¶
[sql] [changed] The implicit conversion of strings to text() constructs
when passed to most builder methods of select() as
well as Query now emits a warning with just the
plain string sent. The textual conversion still proceeds normally,
however. The only method that accepts a string without a warning
are the “label reference” methods like order_by(), group_by();
these functions will now at compile time attempt to resolve a single
string argument to a column or label expression present in the
selectable; if none is located, the expression still renders, but
you get the warning again. The rationale here is that the implicit
conversion from string to text is more unexpected than not these days,
and it is better that the user send more direction to the Core / ORM
when passing a raw string as to what direction should be taken.
Core/ORM tutorials have been updated to go more in depth as to how text
is handled.
References: #2992
[sql] [bug] Fixed bug in Enum and other SchemaType
subclasses where direct association of the type with a
MetaData would lead to a hang when events
(like create events) were emitted on the MetaData.¶
This change is also backported to: 0.9.7, 0.8.7
References: #3124
[sql] [bug] Fixed a bug within the custom operator plus TypeEngine.with_variant()
system, whereby using a TypeDecorator in conjunction with
variant would fail with an MRO error when a comparison operator was used.¶
This change is also backported to: 0.9.7, 0.8.7
References: #3102
[sql] [bug] Fixed bug in INSERT..FROM SELECT construct where selecting from a UNION would wrap the union in an anonymous (e.g. unlabeled) subquery.¶
This change is also backported to: 0.9.5, 0.8.7
References: #3044
[sql] [bug] Fixed bug where Table.update() and Table.delete()
would produce an empty WHERE clause when an empty and_()
or or_() or other blank expression were applied. This is
now consistent with that of select().¶
This change is also backported to: 0.9.5, 0.8.7
References: #3045
[sql] [bug] Added the native_enum flag to the __repr__() output
of Enum, which is mostly important when using it with
Alembic autogenerate. Pull request courtesy Dimitris Theodorou.¶
This change is also backported to: 0.9.9
[sql] [bug] Fixed bug where using a TypeDecorator that implemented
a type that was also a TypeDecorator would fail with
Python’s “Cannot create a consistent method resolution order (MRO)”
error, when any kind of SQL comparison expression were used against
an object using this type.¶
This change is also backported to: 0.9.9
References: #3278
[sql] [bug] Fixed issue where the columns from a SELECT embedded in an INSERT, either through the values clause or as a “from select”, would pollute the column types used in the result set produced by the RETURNING clause when columns from both statements shared the same name, leading to potential errors or mis-adaptation when retrieving the returning rows.¶
This change is also backported to: 0.9.9
References: #3248
[sql] [bug] Fixed bug where a fair number of SQL elements within
the sql package would fail to __repr__() successfully,
due to a missing description attribute that would then invoke
a recursion overflow when an internal AttributeError would then
re-invoke __repr__().¶
This change is also backported to: 0.9.8
References: #3195
[sql] [bug] An adjustment to table/index reflection such that if an index reports a column that isn’t found to be present in the table, a warning is emitted and the column is skipped. This can occur for some special system column situations as has been observed with Oracle.¶
This change is also backported to: 0.9.8
References: #3180
[sql] [bug] Fixed bug in CTE where literal_binds compiler argument would not
be always be correctly propagated when one CTE referred to another
aliased CTE in a statement.¶
This change is also backported to: 0.9.8
References: #3154
[sql] [bug] Fixed 0.9.7 regression caused by #3067 in conjunction with
a mis-named unit test such that so-called “schema” types like
Boolean and Enum could no longer be pickled.¶
This change is also backported to: 0.9.8
[sql] [bug] Fix bug in naming convention feature where using a check
constraint convention that includes constraint_name would
then force all Boolean and Enum types to
require names as well, as these implicitly create a
constraint, even if the ultimate target backend were one that does
not require generation of the constraint such as PostgreSQL.
The mechanics of naming conventions for these particular
constraints has been reorganized such that the naming
determination is done at DDL compile time, rather than at
constraint/table construction time.¶
This change is also backported to: 0.9.7
References: #3067
[sql] [bug] Fixed bug in common table expressions whereby positional bound parameters could be expressed in the wrong final order when CTEs were nested in certain ways.¶
This change is also backported to: 0.9.7
References: #3090
[sql] [bug] Fixed bug where multi-valued Insert construct would fail
to check subsequent values entries beyond the first one given
for literal SQL expressions.¶
This change is also backported to: 0.9.7
References: #3069
[sql] [bug] Added a “str()” step to the dialect_kwargs iteration for Python version < 2.6.5, working around the “no unicode keyword arg” bug as these args are passed along as keyword args within some reflection processes.¶
This change is also backported to: 0.9.7
References: #3123
[sql] [bug] The TypeEngine.with_variant() method will now accept a
type class as an argument which is internally converted to an
instance, using the same convention long established by other
constructs such as Column.¶
This change is also backported to: 0.9.7
References: #3122
[sql] [bug] The Column.nullable flag is implicitly set to False
when that Column is referred to in an explicit
PrimaryKeyConstraint for that table. This behavior now
matches that of when the Column itself has the
Column.primary_key flag set to True, which is
intended to be an exactly equivalent case.¶
This change is also backported to: 0.9.5
References: #3023
[sql] [bug] Fixed bug where the Operators.__and__(),
Operators.__or__() and Operators.__invert__()
operator overload methods could not be overridden within a custom
TypeEngine.Comparator implementation.¶
This change is also backported to: 0.9.5
References: #3012
[sql] [bug] Fixed bug in new DialectKWArgs.argument_for() method where
adding an argument for a construct not previously included for any
special arguments would fail.¶
This change is also backported to: 0.9.5
References: #3024
[sql] [bug] Fixed regression introduced in 0.9 where new “ORDER BY <labelname>” feature from #1068 would not apply quoting rules to the label name as rendered in the ORDER BY.¶
This change is also backported to: 0.9.5
[sql] [bug] Restored the import for Function to the sqlalchemy.sql.expression
import namespace, which was removed at the beginning of 0.9.¶
This change is also backported to: 0.9.5
[sql] [bug] The multi-values version of Insert.values() has been
repaired to work more usefully with tables that have Python-
side default values and/or functions, as well as server-side
defaults. The feature will now work with a dialect that uses
“positional” parameters; a Python callable will also be
invoked individually for each row just as is the case with an
“executemany” style invocation; a server- side default column
will no longer implicitly receive the value explicitly
specified for the first row, instead refusing to invoke
without an explicit value.
References: #3288
[sql] [bug] Fixed bug in Table.tometadata() method where the
CheckConstraint associated with a Boolean
or Enum type object would be doubled in the target table.
The copy process now tracks the production of this constraint object
as local to a type object.¶
References: #3260
[sql] [bug] The behavioral contract of the ForeignKeyConstraint.columns
collection has been made consistent; this attribute is now a
ColumnCollection like that of all other constraints and
is initialized at the point when the constraint is associated with
a Table.
References: #3243
[sql] [bug] The Column.key attribute is now used as the source of
anonymous bound parameter names within expressions, to match the
existing use of this value as the key when rendered in an INSERT
or UPDATE statement. This allows Column.key to be used
as a “substitute” string to work around a difficult column name
that doesn’t translate well into a bound parameter name. Note that
the paramstyle is configurable on create_engine() in any case,
and most DBAPIs today support a named and positional style.¶
References: #3245
[sql] [bug] Fixed the name of the PoolEvents.reset.dbapi_connection
parameter as passed to this event; in particular this affects
usage of the “named” argument style for this event. Pull request
courtesy Jason Goldberger.¶
[sql] [bug] Reversing a change that was made in 0.9, the “singleton” nature
of the “constants” null(), true(), and false()
has been reverted. These functions returning a “singleton” object
had the effect that different instances would be treated as the
same regardless of lexical use, which in particular would impact
the rendering of the columns clause of a SELECT statement.
References: #3170
[sql] [bug] [engine] Fixed bug where a “branched” connection, that is the kind you get
when you call Connection.connect(), would not share invalidation
status with the parent. The architecture of branching has been tweaked
a bit so that the branched connection defers to the parent for
all invalidation status and operations.¶
References: #3215
[sql] [bug] [engine] Fixed bug where a “branched” connection, that is the kind you get
when you call Connection.connect(), would not share transaction
status with the parent. The architecture of branching has been tweaked
a bit so that the branched connection defers to the parent for
all transactional status and operations.¶
References: #3190
[sql] [bug] Using Insert.from_select() now implies inline=True
on insert(). This helps to fix a bug where an
INSERT…FROM SELECT construct would inadvertently be compiled
as “implicit returning” on supporting backends, which would
cause breakage in the case of an INSERT that inserts zero rows
(as implicit returning expects a row), as well as arbitrary
return data in the case of an INSERT that inserts multiple
rows (e.g. only the first row of many).
A similar change is also applied to an INSERT..VALUES
with multiple parameter sets; implicit RETURNING will no longer emit
for this statement either. As both of these constructs deal
with variable numbers of rows, the
ResultProxy.inserted_primary_key accessor does not
apply. Previously, there was a documentation note that one
may prefer inline=True with INSERT..FROM SELECT as some databases
don’t support returning and therefore can’t do “implicit” returning,
but there’s no reason an INSERT…FROM SELECT needs implicit returning
in any case. Regular explicit Insert.returning() should
be used to return variable numbers of result rows if inserted
data is needed.¶
References: #3169
[sql] [enhancement] Custom dialects that implement GenericTypeCompiler can
now be constructed such that the visit methods receive an indication
of the owning expression object, if any. Any visit method that
accepts keyword arguments (e.g. **kw) will in most cases
receive a keyword argument type_expression, referring to the
expression object that the type is contained within. For columns
in DDL, the dialect’s compiler class may need to alter its
get_column_specification() method to support this as well.
The UserDefinedType.get_col_spec() method will also receive
type_expression if it provides **kw in its argument
signature.¶
References: #3074
[schema] [feature] The DDL generation system of MetaData.create_all()
and MetaData.drop_all() has been enhanced to in most
cases automatically handle the case of mutually dependent
foreign key constraints; the need for the
ForeignKeyConstraint.use_alter flag is greatly
reduced. The system also works for constraints which aren’t given
a name up front; only in the case of DROP is a name required for
at least one of the constraints involved in the cycle.
References: #3282
[schema] [feature] Added a new accessor Table.foreign_key_constraints
to complement the Table.foreign_keys collection,
as well as ForeignKeyConstraint.referred_table.¶
[schema] [bug] The CheckConstraint construct now supports naming
conventions that include the token %(column_0_name)s; the
constraint expression is scanned for columns. Additionally,
naming conventions for check constraints that don’t include the
%(constraint_name)s token will now work for SchemaType-
generated constraints, such as those of Boolean and
Enum; this stopped working in 0.9.7 due to #3067.
[postgresql] [feature] Added support for the CONCURRENTLY keyword with PostgreSQL
indexes, established using postgresql_concurrently. Pull
request courtesy Iuri de Silvio.
See also
This change is also backported to: 0.9.9
[postgresql] [feature] [pg8000] Support is added for “sane multi row count” with the pg8000 driver, which applies mostly to when using versioning with the ORM. The feature is version-detected based on pg8000 1.9.14 or greater in use. Pull request courtesy Tony Locke.¶
This change is also backported to: 0.9.8
[postgresql] [feature] Added kw argument postgresql_regconfig to the
ColumnOperators.match() operator, allows the “reg config” argument
to be specified to the to_tsquery() function emitted.
Pull request courtesy Jonathan Vanasco.¶
This change is also backported to: 0.9.7
References: #3078
[postgresql] [feature] Added support for PostgreSQL JSONB via JSONB. Pull request
courtesy Damian Dimmich.¶
This change is also backported to: 0.9.7
[postgresql] [feature] Added support for AUTOCOMMIT isolation level when using the pg8000 DBAPI. Pull request courtesy Tony Locke.¶
This change is also backported to: 0.9.5
[postgresql] [feature] Added a new flag ARRAY.zero_indexes to the PostgreSQL
ARRAY type. When set to True, a value of one will be
added to all array index values before passing to the database, allowing
better interoperability between Python style zero-based indexes and
PostgreSQL one-based indexes. Pull request courtesy Alexey Terentev.¶
This change is also backported to: 0.9.5
References: #2785
[postgresql] [feature] The PG8000 dialect now supports the
create_engine.encoding parameter, by setting up
the client encoding on the connection which is then intercepted
by pg8000. Pull request courtesy Tony Locke.¶
[postgresql] [feature] Added support for PG8000’s native JSONB feature. Pull request courtesy Tony Locke.¶
[postgresql] [feature] [pypy] Added support for the psycopg2cffi DBAPI on pypy. Pull request courtesy shauns.
¶References: #3052
[postgresql] [feature] Added support for the FILTER keyword as applied to aggregate functions, supported by PostgreSQL 9.4. Pull request courtesy Ilja Everilä.
See also
[postgresql] [feature] Support has been added for reflection of materialized views
and foreign tables, as well as support for materialized views
within Inspector.get_view_names(), and a new method
PGInspector.get_foreign_table_names() available on the
PostgreSQL version of Inspector. Pull request courtesy
Rodrigo Menezes.
References: #2891
[postgresql] [feature] Added support for PG table options TABLESPACE, ON COMMIT,
WITH(OUT) OIDS, and INHERITS, when rendering DDL via
the Table construct. Pull request courtesy
malikdiarra.
See also
References: #2051
[postgresql] [feature] Added new method PGInspector.get_enums(), when using the
inspector for PostgreSQL will provide a list of ENUM types.
Pull request courtesy Ilya Pekelny.¶
[postgresql] [bug] Added the hashable=False flag to the PG HSTORE type, which
is needed to allow the ORM to skip over trying to “hash” an ORM-mapped
HSTORE column when requesting it in a mixed column/entity list.
Patch courtesy Gunnlaugur Þór Briem.¶
This change is also backported to: 0.9.5, 0.8.7
References: #3053
[postgresql] [bug] Added a new “disconnect” message “connection has been closed unexpectedly”. This appears to be related to newer versions of SSL. Pull request courtesy Antti Haapala.¶
This change is also backported to: 0.9.5, 0.8.7
[postgresql] [bug] Repaired support for PostgreSQL UUID types in conjunction with
the ARRAY type when using psycopg2. The psycopg2 dialect now
employs use of the psycopg2.extras.register_uuid() hook
so that UUID values are always passed to/from the DBAPI as
UUID() objects. The UUID.as_uuid flag is still
honored, except with psycopg2 we need to convert returned
UUID objects back into strings when this is disabled.¶
This change is also backported to: 0.9.9
References: #2940
[postgresql] [bug] Added support for the postgresql.JSONB datatype when
using psycopg2 2.5.4 or greater, which features native conversion
of JSONB data so that SQLAlchemy’s converters must be disabled;
additionally, the newly added psycopg2 extension
extras.register_default_jsonb is used to establish a JSON
deserializer passed to the dialect via the json_deserializer
argument. Also repaired the PostgreSQL integration tests which
weren’t actually round-tripping the JSONB type as opposed to the
JSON type. Pull request courtesy Mateusz Susik.¶
This change is also backported to: 0.9.9
[postgresql] [bug] Repaired the use of the “array_oid” flag when registering the
HSTORE type with older psycopg2 versions < 2.4.3, which does not
support this flag, as well as use of the native json serializer
hook “register_default_json” with user-defined json_deserializer
on psycopg2 versions < 2.5, which does not include native json.¶
This change is also backported to: 0.9.9
[postgresql] [bug] Fixed bug where PostgreSQL dialect would fail to render an
expression in an Index that did not correspond directly
to a table-bound column; typically when a text() construct
was one of the expressions within the index; or could misinterpret the
list of expressions if one or more of them were such an expression.¶
This change is also backported to: 0.9.9
References: #3174
[postgresql] [bug] A revisit to this issue first patched in 0.9.5, apparently
psycopg2’s .closed accessor is not as reliable as we assumed,
so we have added an explicit check for the exception messages
“SSL SYSCALL error: Bad file descriptor” and
“SSL SYSCALL error: EOF detected” when detecting an
is-disconnect scenario. We will continue to consult psycopg2’s
connection.closed as a first check.¶
This change is also backported to: 0.9.8
References: #3021
[postgresql] [bug] Fixed bug where PostgreSQL JSON type was not able to persist or
otherwise render a SQL NULL column value, rather than a JSON-encoded
'null'. To support this case, changes are as follows:
null() can now be specified, which will always
result in a NULL value resulting in the statement.JSON.none_as_null is added, which
when True indicates that the Python None value should be
persisted as SQL NULL, rather than JSON-encoded 'null'.Retrival of NULL as None is also repaired for DBAPIs other than psycopg2, namely pg8000.
¶This change is also backported to: 0.9.8
References: #3159
[postgresql] [bug] The exception wrapping system for DBAPI errors can now accommodate
non-standard DBAPI exceptions, such as the psycopg2
TransactionRollbackError. These exceptions will now be raised
using the closest available subclass in sqlalchemy.exc, in the
case of TransactionRollbackError, sqlalchemy.exc.OperationalError.¶
This change is also backported to: 0.9.8
References: #3075
[postgresql] [bug] Fixed bug in postgresql.array object where comparison
to a plain Python list would fail to use the correct array constructor.
Pull request courtesy Andrew.¶
This change is also backported to: 0.9.8
References: #3141
[postgresql] [bug] Added a supported FunctionElement.alias() method to functions,
e.g. the func construct. Previously, behavior for this method
was undefined. The current behavior mimics that of pre-0.9.4,
which is that the function is turned into a single-column FROM
clause with the given alias name, where the column itself is
anonymously named.¶
This change is also backported to: 0.9.8
References: #3137
[postgresql] [bug] [pg8000] Fixed bug introduced in 0.9.5 by new pg8000 isolation level feature where engine-level isolation level parameter would raise an error on connect.¶
This change is also backported to: 0.9.7
References: #3134
[postgresql] [bug] The psycopg2 .closed accessor is now consulted when determining
if an exception is a “disconnect” error; ideally, this should remove
the need for any other inspection of the exception message to detect
disconnect, however we will leave those existing messages in place
as a fallback. This should be able to handle newer cases like
“SSL EOF” conditions. Pull request courtesy Dirk Mueller.¶
This change is also backported to: 0.9.5
References: #3021
[postgresql] [bug] The PostgreSQL postgresql.ENUM type will emit a
DROP TYPE instruction when a plain table.drop() is called,
assuming the object is not associated directly with a
MetaData object. In order to accommodate the use case of
an enumerated type shared between multiple tables, the type should
be associated directly with the MetaData object; in this
case the type will only be created at the metadata level, or if
created directly. The rules for create/drop of
PostgreSQL enumerated types have been highly reworked in general.
References: #3319
[postgresql] [bug] The PGDialect.has_table() method will now query against
pg_catalog.pg_table_is_visible(c.oid), rather than testing
for an exact schema match, when the schema name is None; this
so that the method will also illustrate that temporary tables
are present. Note that this is a behavioral change, as PostgreSQL
allows a non-temporary table to silently overwrite an existing
temporary table of the same name, so this changes the behavior
of checkfirst in that unusual scenario.
References: #3264
[postgresql] [enhancement] Added a new type postgresql.OID to the PostgreSQL dialect.
While “oid” is generally a private type within PG that is not exposed
in modern versions, there are some PG use cases such as large object
support where these types might be exposed, as well as within some
user-reported schema reflection use cases.¶
This change is also backported to: 0.9.5
References: #3002
[mysql] [feature] The MySQL dialect now renders TIMESTAMP with NULL / NOT NULL in
all cases, so that MySQL 5.6.6 with the
explicit_defaults_for_timestamp flag enabled will
will allow TIMESTAMP to continue to work as expected when
nullable=False. Existing applications are unaffected as
SQLAlchemy has always emitted NULL for a TIMESTAMP column that
is nullable=True.
References: #3155
[mysql] [feature] Updated the “supports_unicode_statements” flag to True for MySQLdb and Pymysql under Python 2. This refers to the SQL statements themselves, not the parameters, and affects issues such as table and column names using non-ASCII characters. These drivers both appear to support Python 2 Unicode objects without issue in modern versions.¶
References: #3121
[mysql] [bug] MySQL error 2014 “commands out of sync” appears to be raised as a ProgrammingError, not OperationalError, in modern MySQL-Python versions; all MySQL error codes that are tested for “is disconnect” are now checked within OperationalError and ProgrammingError regardless.¶
This change is also backported to: 0.9.7, 0.8.7
References: #3101
[mysql] [bug] Fixed bug where column names added to mysql_length parameter
on an index needed to have the same quoting for quoted names in
order to be recognized. The fix makes the quotes optional but
also provides the old behavior for backwards compatibility with those
using the workaround.¶
This change is also backported to: 0.9.5, 0.8.7
References: #3085
[mysql] [bug] Added support for reflecting tables where an index includes KEY_BLOCK_SIZE using an equal sign. Pull request courtesy Sean McGivern.¶
This change is also backported to: 0.9.5, 0.8.7
[mysql] [bug] Added a version check to the MySQLdb dialect surrounding the check for ‘utf8_bin’ collation, as this fails on MySQL server < 5.0.¶
This change is also backported to: 0.9.9
References: #3274
[mysql] [bug] [mysqlconnector] Mysqlconnector as of version 2.0, probably as a side effect of
the python 3 merge, now does not expect percent signs (e.g.
as used as the modulus operator and others) to be doubled,
even when using the “pyformat” bound parameter format (this
change is not documented by Mysqlconnector). The dialect now
checks for py2k and for mysqlconnector less than version 2.0
when detecting if the modulus operator should be rendered as
%% or %.¶
This change is also backported to: 0.9.8
[mysql] [bug] [mysqlconnector] Unicode SQL is now passed for MySQLconnector version 2.0 and above; for Py2k and MySQL < 2.0, strings are encoded.¶
This change is also backported to: 0.9.8
[mysql] [bug] The MySQL dialect now supports CAST on types that are constructed
as TypeDecorator objects.¶
[mysql] [bug] A warning is emitted when cast() is used with the MySQL
dialect on a type where MySQL does not support CAST; MySQL only
supports CAST on a subset of datatypes. SQLAlchemy has for a long
time just omitted the CAST for unsupported types in the case of
MySQL. While we don’t want to change this now, we emit a warning
to show that it’s taken place. A warning is also emitted when
a CAST is used with an older MySQL version (< 4) that doesn’t support
CAST at all, it’s skipped in this case as well.¶
References: #3237
[mysql] [bug] The mysql.SET type has been overhauled to no longer
assume that the empty string, or a set with a single empty string
value, is in fact a set with a single empty string; instead, this
is by default treated as the empty set. In order to handle persistence
of a mysql.SET that actually wants to include the blank
value '' as a legitimate value, a new bitwise operational mode
is added which is enabled by the
mysql.SET.retrieve_as_bitwise flag, which will persist
and retrieve values unambiguously using their bitflag positioning.
Storage and retrieval of unicode values for driver configurations
that aren’t converting unicode natively is also repaired.
References: #3283
[mysql] [bug] The ColumnOperators.match() operator is now handled such that the
return type is not strictly assumed to be boolean; it now
returns a Boolean subclass called MatchType.
The type will still produce boolean behavior when used in Python
expressions, however the dialect can override its behavior at
result time. In the case of MySQL, while the MATCH operator
is typically used in a boolean context within an expression,
if one actually queries for the value of a match expression, a
floating point value is returned; this value is not compatible
with SQLAlchemy’s C-based boolean processor, so MySQL’s result-set
behavior now follows that of the Float type.
A new operator object notmatch_op is also added to better allow
dialects to define the negation of a match operation.
References: #3263
[mysql] [bug] MySQL boolean symbols “true”, “false” work again. 0.9’s change
in #2682 disallowed the MySQL dialect from making use of the
“true” and “false” symbols in the context of “IS” / “IS NOT”, but
MySQL supports this syntax even though it has no boolean type.
MySQL remains “non native boolean”, but the true()
and false() symbols again produce the
keywords “true” and “false”, so that an expression like
column.is_(true()) again works on MySQL.
References: #3186
[mysql] [bug] The MySQL dialect will now disable ConnectionEvents.handle_error()
events from firing for those statements which it uses internally
to detect if a table exists or not. This is achieved using an
execution option skip_user_error_events that disables the handle
error event for the scope of that execution. In this way, user code
that rewrites exceptions doesn’t need to worry about the MySQL
dialect or other dialects that occasionally need to catch
SQLAlchemy specific exceptions.¶
[mysql] [bug] Changed the default value of “raise_on_warnings” to False for MySQLconnector. This was set at True for some reason. The “buffered” flag unfortunately must stay at True as MySQLconnector does not allow a cursor to be closed unless all results are fully fetched.¶
References: #2515
[mysql] [change] The gaerdbms dialect is no longer necessary, and emits a
deprecation warning. Google now recommends using the MySQLdb
dialect directly.¶
This change is also backported to: 0.9.9
References: #3275
[sqlite] [feature] Added support for partial indexes (e.g. with a WHERE clause) on SQLite. Pull request courtesy Kai Groner.
See also
This change is also backported to: 0.9.9
[sqlite] [feature] Added a new SQLite backend for the SQLCipher backend. This backend provides for encrypted SQLite databases using the pysqlcipher Python driver, which is very similar to the pysqlite driver.
See also
This change is also backported to: 0.9.9
[sqlite] [bug] When selecting from a UNION using an attached database file, the pysqlite driver reports column names in cursor.description as ‘dbname.tablename.colname’, instead of ‘tablename.colname’ as it normally does for a UNION (note that it’s supposed to just be ‘colname’ for both, but we work around it). The column translation logic here has been adjusted to retrieve the rightmost token, rather than the second token, so it works in both cases. Workaround courtesy Tony Roberts.¶
This change is also backported to: 0.9.8
References: #3211
[sqlite] [bug] Fixed a SQLite join rewriting issue where a subquery that is embedded as a scalar subquery such as within an IN would receive inappropriate substitutions from the enclosing query, if the same table were present inside the subquery as were in the enclosing query such as in a joined inheritance scenario.¶
This change is also backported to: 0.9.7
References: #3130
[sqlite] [bug] UNIQUE and FOREIGN KEY constraints are now fully reflected on SQLite both with and without names. Previously, foreign key names were ignored and unnamed unique constraints were skipped. Thanks to Jon Nelson for assistance with this.¶
[sqlite] [bug] The SQLite dialect, when using the sqlite.DATE,
sqlite.TIME,
or sqlite.DATETIME types, and given a storage_format that
only renders numbers, will render the types in DDL as
DATE_CHAR, TIME_CHAR, and DATETIME_CHAR, so that despite the
lack of alpha characters in the values, the column will still
deliver the “text affinity”. Normally this is not needed, as the
textual values within the default storage formats already
imply text.
See also
References: #3257
[sqlite] [bug] SQLite now supports reflection of unique constraints from temp tables; previously, this would fail with a TypeError. Pull request courtesy Johannes Erdfelt.
See also
SQLite/Oracle have distinct methods for temporary table/view name reporting - changes regarding SQLite temporary table and view reflection.
References: #3203
[sqlite] [bug] Added Inspector.get_temp_table_names() and
Inspector.get_temp_view_names(); currently, only the
SQLite and Oracle dialects support these methods. The return of
temporary table and view names has been removed from SQLite and
Oracle’s version of Inspector.get_table_names() and
Inspector.get_view_names(); other database backends cannot
support this information (such as MySQL), and the scope of operation
is different in that the tables can be local to a session and
typically aren’t supported in remote schemas.
References: #3204
[mssql] [feature] Enabled “multivalues insert” for SQL Server 2008. Pull request courtesy Albert Cervin. Also expanded the checks for “IDENTITY INSERT” mode to include when the identity key is present in the VALUEs clause of the statement.¶
This change is also backported to: 0.9.7
[mssql] [feature] SQL Server 2012 now recommends VARCHAR(max), NVARCHAR(max),
VARBINARY(max) for large text/binary types. The MSSQL dialect will
now respect this based on version detection, as well as the new
deprecate_large_types flag.
See also
References: #3039
[mssql] [changed] The hostname-based connection format for SQL Server when using pyodbc will no longer specify a default “driver name”, and a warning is emitted if this is missing. The optimal driver name for SQL Server changes frequently and is per-platform, so hostname based connections need to specify this. DSN-based connections are preferred.
¶References: #3182
[mssql] [bug] Added statement encoding to the “SET IDENTITY_INSERT” statements which operate when an explicit INSERT is being interjected into an IDENTITY column, to support non-ascii table identifiers on drivers such as pyodbc + unix + py2k that don’t support unicode statements.¶
This change is also backported to: 0.9.7, 0.8.7
[mssql] [bug] In the SQL Server pyodbc dialect, repaired the implementation
for the description_encoding dialect parameter, which when
not explicitly set was preventing cursor.description from
being parsed correctly in the case of result sets that
contained names in alternate encodings. This parameter
shouldn’t be needed going forward.¶
This change is also backported to: 0.9.7, 0.8.7
References: #3091
[mssql] [bug] Fixed the version string detection in the pymssql dialect to work with Microsoft SQL Azure, which changes the word “SQL Server” to “SQL Azure”.¶
This change is also backported to: 0.9.8
References: #3151
[mssql] [bug] Revised the query used to determine the current default schema name
to use the database_principal_id() function in conjunction with
the sys.database_principals view so that we can determine
the default schema independently of the type of login in progress
(e.g., SQL Server, Windows, etc).¶
This change is also backported to: 0.9.5
References: #3025
[oracle] [feature] Added support for cx_oracle connections to a specific service
name, as opposed to a tns name, by passing ?service_name=<name>
to the URL. Pull request courtesy Sławomir Ehlert.¶
[oracle] [feature] New Oracle DDL features for tables, indexes: COMPRESS, BITMAP. Patch courtesy Gabor Gombas.¶
[oracle] [feature] Added support for CTEs under Oracle. This includes some tweaks
to the aliasing syntax, as well as a new CTE feature
CTE.suffix_with(), which is useful for adding in special
Oracle-specific directives to the CTE.
See also
References: #3220
[oracle] [feature] Added support for the Oracle table option ON COMMIT.¶
[oracle] [bug] Fixed long-standing bug in Oracle dialect where bound parameter names that started with numbers would not be quoted, as Oracle doesn’t like numerics in bound parameter names.¶
This change is also backported to: 0.9.8
References: #2138
[oracle] [bug] [tests] Fixed bug in oracle dialect test suite where in one test, ‘username’ was assumed to be in the database URL, even though this might not be the case.¶
This change is also backported to: 0.9.7
References: #3128
[oracle] [bug] An alias name will be properly quoted when referred to using the
%(name)s token inside the Select.with_hint() method.
Previously, the Oracle backend hadn’t implemented this quoting.¶
[feature] [examples] Added a new example illustrating materialized paths, using the latest relationship features. Example courtesy Jack Zhou.¶
This change is also backported to: 0.9.5
[feature] [ext] Added a new extension suite sqlalchemy.ext.baked. This
simple but unusual system allows for a dramatic savings in Python
overhead for the construction and processing of orm Query
objects, from query construction up through rendering of a string
SQL statement.
See also
References: #3054
[feature] [examples] A new suite of examples dedicated to providing a detailed study into performance of SQLAlchemy ORM and Core, as well as the DBAPI, from multiple perspectives. The suite runs within a container that provides built in profiling displays both through console output as well as graphically via the RunSnake tool.
See also
[feature] [ext] The sqlalchemy.ext.automap extension will now set
cascade="all, delete-orphan" automatically on a one-to-many
relationship/backref where the foreign key is detected as containing
one or more non-nullable columns. This argument is present in the
keywords passed to automap.generate_relationship() in this
case and can still be overridden. Additionally, if the
ForeignKeyConstraint specifies ondelete="CASCADE"
for a non-nullable or ondelete="SET NULL" for a nullable set
of columns, the argument passive_deletes=True is also added to the
relationship. Note that not all backends support reflection of
ondelete, but backends that do include PostgreSQL and MySQL.¶
References: #3210
[removed] The Drizzle dialect has been removed from the Core; it is now available as sqlalchemy-drizzle, an independent, third party dialect. The dialect is still based almost entirely off of the MySQL dialect present in SQLAlchemy.
¶[bug] [declarative] The __mapper_args__ dictionary is copied from a declarative
mixin or abstract class when accessed, so that modifications made
to this dictionary by declarative itself won’t conflict with that
of other mappings. The dictionary is modified regarding the
version_id_col and polymorphic_on arguments, replacing the
column within with the one that is officially mapped to the local
class/table.¶
This change is also backported to: 0.9.5, 0.8.7
References: #3062
[bug] [ext] Fixed bug in mutable extension where MutableDict did not
report change events for the setdefault() dictionary operation.¶
This change is also backported to: 0.9.5, 0.8.7
[bug] [ext] Fixed bug where MutableDict.setdefault() didn’t return the
existing or new value (this bug was not released in any 0.8 version).
Pull request courtesy Thomas Hervé.¶
This change is also backported to: 0.9.5, 0.8.7
[bug] [ext] [py3k] Fixed bug where the association proxy list class would not interpret slices correctly under Py3K. Pull request courtesy Gilles Dartiguelongue.¶
This change is also backported to: 0.9.9
[bug] [examples] Updated the Versioning with a History Table example such that mapped columns are re-mapped to match column names as well as grouping of columns; in particular, this allows columns that are explicitly grouped in a same-column-named joined inheritance scenario to be mapped in the same way in the history mappings, avoiding warnings added in the 0.9 series regarding this pattern and allowing the same view of attribute keys.¶
This change is also backported to: 0.9.9
[bug] [examples] Fixed a bug in the examples/generic_associations/discriminator_on_association.py example, where the subclasses of AddressAssociation were not being mapped as “single table inheritance”, leading to problems when trying to use the mappings further.¶
This change is also backported to: 0.9.9
[bug] [declarative] Fixed an unlikely race condition observed in some exotic end-user setups, where the attempt to check for “duplicate class name” in declarative would hit upon a not-totally-cleaned-up weak reference related to some other class being removed; the check here now ensures the weakref still references an object before calling upon it further.¶
This change is also backported to: 0.9.8
References: #3208
[bug] [ext] Fixed bug in ordering list where the order of items would be thrown off during a collection replace event, if the reorder_on_append flag were set to True. The fix ensures that the ordering list only impacts the list that is explicitly associated with the object.¶
This change is also backported to: 0.9.8
References: #3191
[bug] [ext] Fixed bug where ext.mutable.MutableDict
failed to implement the update() dictionary method, thus
not catching changes. Pull request courtesy Matt Chisholm.¶
This change is also backported to: 0.9.8
[bug] [ext] Fixed bug where a custom subclass of ext.mutable.MutableDict
would not show up in a “coerce” operation, and would instead
return a plain ext.mutable.MutableDict. Pull request
courtesy Matt Chisholm.¶
This change is also backported to: 0.9.8
[bug] [pool] Fixed bug in connection pool logging where the “connection checked out”
debug logging message would not emit if the logging were set up using
logging.setLevel(), rather than using the echo_pool flag.
Tests to assert this logging have been added. This is a
regression that was introduced in 0.9.0.¶
This change is also backported to: 0.9.8
References: #3168
[bug] [tests] Fixed bug where “python setup.py test” wasn’t calling into distutils appropriately, and errors would be emitted at the end of the test suite.¶
This change is also backported to: 0.9.7
[bug] [declarative] Fixed bug when the declarative __abstract__ flag was not being
distinguished for when it was actually the value False.
The __abstract__ flag needs to actually evaluate to a True
value at the level being tested.¶
This change is also backported to: 0.9.7
References: #3097
[bug] [testsuite] In public test suite, changed to use of String(40) from
less-supported Text in StringTest.test_literal_backslashes.
Pullreq courtesy Jan.¶
This change is also backported to: 0.9.5
[bug] [py3k] [tests] Corrected for some deprecation warnings involving the imp
module and Python 3.3 or greater, when running tests. Pull
request courtesy Matt Chisholm.¶
This change is also backported to: 0.9.5
References: #2830