"auto increment" column has been changed, such that autoincrement
is no longer implicitly enabled for a :class:`.Table` that has a
composite primary key. In order to accommodate being able to enable
autoincrement for a composite PK member column while at the same time
maintaining SQLAlchemy's long standing behavior of enabling
implicit autoincrement for a single integer primary key, a third
state has been added to the :paramref:`.Column.autoincrement` parameter
``"auto"``, which is now the default. fixes#3216
- The MySQL dialect no longer generates an extra "KEY" directive when
generating CREATE TABLE DDL for a table using InnoDB with a
composite primary key with AUTO_INCREMENT on a column that isn't the
first column; to overcome InnoDB's limitation here, the PRIMARY KEY
constraint is now generated with the AUTO_INCREMENT column placed
first in the list of columns.
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.
fixes#3300
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.
fixes#3230
when we do a get; we return the None as always but we leave the dict blank
and the loader callable still in place. The case for this implicit get on a pending object is not
super common and there really should be no change in state at all when this
operation proceeds. This change is more dramatic as it reverses
a behavior SQLA has had since the first release.
fixes#3061
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.
fixes#3042
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 :meth:`.Operators.like` operator has
also been added to the list of valid operators to use in a primaryjoin
condition. fixes#3029
flag allows a custom op from :meth:`.Operators.op` to be considered
as a "comparison" operator, thus usable for custom
:paramref:`.relationship.primaryjoin` conditions.
target of :paramref:`.relationship.secondary` for the purposes
of creating very complex :func:`.relationship` join conditions.
The change includes adjustments to query joining, joined eager loading
to not render a SELECT subquery, changes to lazy loading such that
the "secondary" target is properly included in the SELECT, and
changes to declarative to better support specification of a
join() object with classes as targets.
attribute history from being written on behalf of the target attribute.
This has the effect of the object not being written to the
Session.dirty list if it is mutated. Previously, the object would
be present in Session.dirty, but no change would take place on behalf
of the modified attribute during flush. The attribute still emits
events such as backref events and user-defined events and will still
receive mutations from backrefs. [ticket:2833]
the import structure of many core modules.
``sqlalchemy.schema`` and ``sqlalchemy.types``
remain in the top-level package, but are now just lists of names
that pull from within ``sqlalchemy.sql``. Their implementations
are now broken out among ``sqlalchemy.sql.type_api``, ``sqlalchemy.sql.sqltypes``,
``sqlalchemy.sql.schema`` and ``sqlalchemy.sql.ddl``, the last of which was
moved from ``sqlalchemy.engine``. ``sqlalchemy.sql.expression`` is also
a namespace now which pulls implementations mostly from ``sqlalchemy.sql.elements``,
``sqlalchemy.sql.selectable``, and ``sqlalchemy.sql.dml``.
Most of the "factory" functions
used to create SQL expression objects have been moved to classmethods
or constructors, which are exposed in ``sqlalchemy.sql.expression``
using a programmatic system. Care has been taken such that all the
original import namespaces remain intact and there should be no impact
on any existing applications. The rationale here was to break out these
very large modules into smaller ones, provide more manageable lists
of function names, to greatly reduce "import cycles" and clarify the
up-front importing of names, and to remove the need for redundant
functions and documentation throughout the expression package.
become an externally usable package but still remains within the main sqlalchemy parent package.
in this system, we use kind of an ugly hack to get the noseplugin imported outside of the
"sqlalchemy" package, while still making it available within sqlalchemy for usage by
third party libraries.
- using new traversal that returns the product of both sides
of a binary, starting to work with (a+b) == (c+d) types of joins.
primaryjoins on functions working
- annotations working, including reversing local/remote when
doing backref
conditions such that foreign key errors are
only considered between the two given tables.
That is, t1.join(t2) will report FK errors
that involve 't1' or 't2', but anything
involving 't3' will be skipped. This affects
join(), as well as ORM relationship and
inherit condition logic. Will keep the more conservative
approach to [ticket:2153] in 0.6.
access to the cls/self.tables/classes registries
- express orm/_base.py ORMTest in terms of engine/_base.py TablesTest,
factor out common steps into TablesTest, remove AltEngineTest as a
separate class. will further consolidate these base classes
in an unusual condition that the join condition
"works" for viewonly but doesn't work for non-viewonly,
and foreign_keys wasn't used - adds "foreign_keys" to
the suggestion. Also add "foreign_keys" to the
suggestion for the generic "direction" error.
outside of "sqlalchemy" and under "test/".
Rationale:
- coverage plugin works without issue, without need for an awkward
additional package install
- command line for "nosetests" isn't polluted with SQLAlchemy options
[ticket:1949]
and column_property(), forces attribute events to
always load the "old" value, so that it's available to
attributes.get_history(). [ticket:1961]
- modernize test_relationship, give test classes meaningful names
emitted when relationship() is configured with
ambiguous arguments. The "foreign_keys"
setting is no longer mentioned, as it is almost
never needed and it is preferable users set up
correct ForeignKey metadata, which is now the
recommendation. If 'foreign_keys'
is used and is incorrect, the message suggests
the attribute is probably unnecessary. Docs
for the attribute are beefed up. This
because all confused relationship() users on the
ML appear to be attempting to use foreign_keys
due to the message, which only confuses them
further since Table metadata is much clearer.
- If the "secondary" table has no ForeignKey metadata
and no foreign_keys is set, even though the
user is passing screwed up information, it is assumed
that primary/secondaryjoin expressions should
consider only and all cols in "secondary" to be
foreign. It's not possible with "secondary" for
the foreign keys to be elsewhere in any case.
A warning is now emitted instead of an error,
and the mapping succeeds. [ticket:1877]
- fixed incorrect "Alternate Collection Mappings" reference
in the docs, not sure if someone wants to reference
"Rows that Point to Themselves" function
- "Collection Mapping" is "Advanced Collection Mapping", this
section is troublesome since nobody really needs it but it
is public API
Mike Bayer