new automap extension would fail if classes
were pre-arranged in single or potentially joined inheritance patterns.
The repaired joined inheritance issue could also potentially apply when
using :class:`.DeferredReflection` as well.
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.
:class:`.DeferredReflection`
to define classes pending for reflection, if some subset of those
classes were discarded before the :meth:`.DeferredReflection.prepare`
method were called to reflect and map the class, a strong reference
to the class would remain held within the declarative internals.
This internal collection of "classes to map" now uses weak
references against the classes themselves.
attribute on declarative to simply refer directly to an :class:`.InstrumentedAttribute`
on a superclass or on the class itself, and it
acts more or less like a synonym; in 0.9, this fails to set up enough
bookkeeping to keep up with the more liberalized backref logic
from 🎫`2789`. Even though this use case was never directly
considered, it is now detected by declarative at the "setattr()" level
as well as when setting up a subclass, and the mirrored/renamed attribute
is now set up as a :func:`.synonym` instead. [ticket:2900]
:class:`.Column` is mapped multiple times under different properties
(which typically should be a :func:`.synonym` instead) or if two
or more :class:`.Column` objects are given the same name, raising
a warning if this condition is detected. [ticket:2828]
doesn't resolve to a class or mapper has been corrected to work
the same way as when a non-string arg is received, which indicates
the name of the relationship which had the configurational error.
[ticket:2888]
automatic reflection support for the "secondary" table referred
to by a :func:`.relationship`. "secondary", when specified
either as a string table name, or as a :class:`.Table` object with
only a name and :class:`.MetaData` object will also be included
in the reflection process when :meth:`.DeferredReflection.prepare`
is called. [ticket:2865]
- clsregistry._resolver() now uses a stateful _class_resolver()
class in order to handle the work of mapping strings to
objects. This is to provide for simpler extensibility, namely
a ._resolvers collection of ad-hoc name resolution functions;
the DeferredReflection class adds its own resolver here in order
to handle relationship(secondary) names which generate new
Table objects.
instead of relying upon various ``quote=True`` flags being passed around,
these flags are converted into rich string objects with quoting information
included at the point at which they are passed to common schema constructs
like :class:`.Table`, :class:`.Column`, etc. This solves the issue
of various methods that don't correctly honor the "quote" flag such
as :meth:`.Engine.has_table` and related methods. The :class:`.quoted_name`
object is a string subclass that can also be used explicitly if needed;
the object will hold onto the quoting preferences passed and will
also bypass the "name normalization" performed by dialects that
standardize on uppercase symbols, such as Oracle, Firebird and DB2.
The upshot is that the "uppercase" backends can now work with force-quoted
names, such as lowercase-quoted names and new reserved words.
[ticket:2812]
- rework the event system so that event modules load after their
targets, dependencies are reversed
- create an improved strategy lookup system for the ORM
- rework the ORM to have very few import cycles
- move out "importlater" to just util.dependency
- other tricks to cross-populate modules in as clear a way as possible
proxies, they aren't overriding getattr() or setattr() at all. so all the
hardcoded getattr()/setattr() is removed from collections.py. Lots of these
getattr/setattr were against the attributeimpl and decorated functions
and don't seem like they'd ever be needed; for a user that needs special access
to a collection, we can evaulate that use case and add a single point of
"unwrapping", and probably add a hook for it via
InstrumentationManager so that the collection implementation isn't complicated
by it.
by name in a string argument used with ``order_by``,
``primaryjoin``, or similar in :func:`.relationship`,
in addition to column-bound attributes. [ticket:2761]
scalar values, for comparisons to None to also take into account
the association record itself being non-present, in addition to the
existing test for the scalar endpoint on the association record
being NULL. Previously, comparing ``Cls.scalar == None`` would return
records for which ``Cls.associated`` were present and
``Cls.associated.scalar`` is None, but not rows for which
``Cls.associated`` is non-present. More significantly, the
inverse operation ``Cls.scalar != None`` *would* return ``Cls``
rows for which ``Cls.associated`` was non-present.
Additionally, added a special use case where you
can call ``Cls.scalar.has()`` with no arguments,
when ``Cls.scalar`` is a column-based value - this returns whether or
not ``Cls.associated`` has any rows present, regardless of whether
or not ``Cls.associated.scalar`` is NULL or not.
[ticket:2751]
that the "id" passed from the pickler is turned into a string
to prevent against bytes being parsed on Py3K, as well as that
``relationship()`` and ``orm.join()`` constructs are now properly
serialized. [ticket:2698] and some other observed issues.
where since it considers the current class' ``__table__``, was
sensitive to when it was called. This is 0.7's behavior also,
but in 0.7 things tended to "work out" within events like
``__mapper_args__()``. :func:`.has_inherited_table` now only
considers superclasses, so should return the same answer
regarding the current class no matter when it's called
(obviously assuming the state of the superclass).
[ticket:2656]
:meth:`.MutableBase.coerce` method to be used, even though
the code seemed to indicate this intent, so this now works
and a brief example is added. As a side-effect,
the mechanics of this event handler have been changed so that
new :class:`.MutableComposite` types no longer add per-type
global event handlers. Also in 0.7.10
[ticket:2624]
to :class:`.Engine`. This method works similarly to
:class:`.Connection.execution_options` in that it creates
a copy of the parent object which will refer to the new
set of options. The method can be used to build
sharding schemes where each engine shares the same
underlying pool of connections. The method
has been tested against the horizontal shard
recipe in the ORM as well.
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.
between a @declared_attr Column and a
directly-defined Column on a mixin. In both
cases, the Column will be applied to the
declared class' table, but not to that of a
joined inheritance subclass. Previously,
the directly-defined Column would be placed
on both the base and the sub table, which isn't
typically what's desired. [ticket:2565]
CREATE TABLE that provides access to the render for each
Column individually, by constructing a @compiles
function against the new schema.CreateColumn
construct. [ticket:2463]
Mike Bayer