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
- more docs for engine, pool, DDL events
- update DDL sequences documentation to use events
- update DDL() docstring to refer to execute_if()
- document parameters for DDLElement.execute_if()
- add retval=True flag to Engine.on_before_execute(), on_before_cursor_execute().
wrap the function if retval=False, check for appropriate usage of the flag, add
tests.
- remove ScopedSession.mapper and tests entirely
- remove ExtensionCarrier and tests
- change remaining tests that use MapperExtension to use MapperEvents
Treats the given expression as the given type when evaluating
expressions and processing result rows, but does not
affect the generation of SQL, other than an anonymous label.
with declarative is sqlalchemy.ext.declarative.mapperproperty.
Same thing, but moving there since it is more of a
"marker" that's specific to declararative,
not just an attribute technique. [ticket:1915]
- docs about backref cascade
- Another new flag on relationship(), cascade_backrefs,
disables the "save-update" cascade when the event was
initiated on the "reverse" side of a bidirectional
relationship. This is a cleaner behavior so that
many-to-ones can be set on a transient object without
it getting sucked into the child object's session,
while still allowing the forward collection to
cascade. We *might* default this to False in 0.7.
the current state, not the "committed" state,
of foreign and primary key attributes
when issuing SQL, if a flush is not in process.
Previously, only the database-committed state would
be used. In particular, this would cause a many-to-one
get()-on-lazyload operation to fail, as autoflush
is not triggered on these loads when the attributes are
determined and the "committed" state may not be
available. [ticket:1910]
- A new flag on relationship(), load_on_pending, allows
the lazy loader to fire off on pending objects without a
flush taking place, as well as a transient object that's
been manually "attached" to the session. Note that this
flag blocks attribute events from taking place when an
object is loaded, so backrefs aren't available until
after a flush. The flag is only intended for very
specific use cases.
when placed only on the many-to-one side of a
relationship; documentation has been clarified
that passive_updates=False should really be on the
one-to-many side.
- Placing passive_deletes=True on a many-to-one emits
a warning, since you probably intended to put it on
the one-to-many side.
- Added an assertion during flush which ensures
that no NULL-holding identity keys were generated
on "newly persistent" objects.
This can occur when user defined code inadvertently
triggers flushes on not-fully-loaded objects.
Mike Bayer