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| -rw-r--r-- | doc/build/changelog/migration_08.rst | 65 | ||||
| -rw-r--r-- | doc/build/glossary.rst | 1 |
2 files changed, 65 insertions, 1 deletions
diff --git a/doc/build/changelog/migration_08.rst b/doc/build/changelog/migration_08.rst index 08a727a3c..690b0296b 100644 --- a/doc/build/changelog/migration_08.rst +++ b/doc/build/changelog/migration_08.rst @@ -405,6 +405,54 @@ and :meth:`.PropComparator.has`:: :ticket:`2438` :ticket:`1106` +Events Can Be Applied to Unmapped Superclasses +---------------------------------------------- + +Mapper and instance events can now be associated with an unmapped +superclass, where those events will be propagated to subclasses +as those subclasses are mapped. The ``propagate=True`` flag +should be used. This feature allows events to be associated +with a declarative base class:: + + from sqlalchemy.ext.declarative import declarative_base + + Base = declarative_base() + + @event.listens_for("load", Base, propagate=True) + def on_load(target, context): + print "New instance loaded:", target + + # on_load() will be applied to SomeClass + class SomeClass(Base): + __tablename__ = 'sometable' + + # ... + +:ticket:`2585` + +Declarative Distinguishes Between Modules/Packages +-------------------------------------------------- + +A key feature of Declarative is the ability to refer +to other mapped classes using their string name. The +registry of class names is now sensitive to the owning +module and package of a given class. The classes +can be referred to via dotted name in expressions:: + + class Snack(Base): + # ... + + "peanuts":relationship("nuts.Peanut", + primaryjoin="nuts.Peanut.snack_id == Snack.id") + +The resolution allows that any full or partial +disambiguating package name can be used. If the +path to a particular class is still ambiguous, +an error is raised. + +:ticket:`2338` + + New DeferredReflection Feature in Declarative --------------------------------------------- @@ -878,6 +926,21 @@ entity, ``query.correlate(someentity)``. :ticket:`2179` +Repaired the Event Targeting of :class:`.InstrumentationEvents` +---------------------------------------------------------------- + +The :class:`.InstrumentationEvents` series of event targets have +documented that the events will only be fired off according to +the actual class passed as a target. Through 0.7, this wasn't the +case, and any event listener applied to :class:`.InstrumentationEvents` +would be invoked for all classes mapped. In 0.8, additional +logic has been added so that the events will only invoke for those +classes sent in. The ``propagate`` flag here is set to ``True`` +by default as class instrumentation events are typically used to +intercept classes that aren't yet created. + +:ticket:`2590` + No more magic coercion of "=" to IN when comparing to subquery in MS-SQL ------------------------------------------------------------------------ @@ -900,7 +963,7 @@ usual scope so the behavior is removed. :ticket:`2277` Fixed the behavior of :meth:`.Session.is_modified` -------------------------------------------- +-------------------------------------------------- The :meth:`.Session.is_modified` method accepts an argument ``passive`` which basically should not be necessary, the diff --git a/doc/build/glossary.rst b/doc/build/glossary.rst index 41c8db1a0..f0c4cbc00 100644 --- a/doc/build/glossary.rst +++ b/doc/build/glossary.rst @@ -14,6 +14,7 @@ Glossary :sorted: descriptor + descriptors In Python, a descriptor is an object attribute with “binding behavior”, one whose attribute access has been overridden by methods in the `descriptor protocol <http://docs.python.org/howto/descriptor.html>`_. Those methods are __get__(), __set__(), and __delete__(). If any of those methods are defined for an object, it is said to be a descriptor. |