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
attribute will now honor the "passive" flag
passed to it; as this defaults to ``PASSIVE_OFF``, the function will
by default query the database if the value is not present.
This is a behavioral change vs. 0.8. [ticket:2787]
- Added new method :meth:`.AttributeState.load_history`, works like
:attr:`.AttributeState.history` but also fires loader callables.
passes in AliasedInsp and allows more flexibility.
- rework the AliasedClass/AliasedInsp relationship so that AliasedInsp has
all state and functionality. AliasedClass is just a facade.
[ticket:2756]
associated with the ORM or its extensions can be retrieved.
This fulfills the common request of being able to inspect
all :class:`.QueryableAttribute` descriptors in addition to
extension types such as :class:`.hybrid_property` and
:class:`.AssociationProxy`. See :attr:`.Mapper.all_orm_descriptors`.
- paths now store Mapper + MapperProperty now instead of string key,
so that the parent mapper for the property is known, supports same-named
properties on multiple subclasses
- the Mapper within the path is now always relevant to the property
to the right of it. PathRegistry does the translation now, instead
of having all the outside users of PathRegistry worry about it,
to produce a path that is much more consistent. Paths are now
consistent with mappings in all cases. Special logic to get at
"with_polymorphic" structures and such added also.
- AliasedClass now has two modes, "use_mapper_path" and regular;
"use_mapper_path" is for all those situations where we put an AliasedClass
in for a plain class internally, and want it to "path" with the
plain mapper.
- The AliasedInsp is now the first class "entity" for an AliasedClass,
and is passed around internally and used as attr._parententity
and such. it is the AliasedClass analogue for Mapper.
- redefine inspect(Class.attrname).parent to be always an inspectable
target; either Mapper or AliasedInsp
- add most major features to 08 migration, document, link
1. all Comparators now have "parent" which is always the parent mapper
or AliasedClass instance
2. only RelationshipProperty.Comparator has "mapper" now, which
is the target mapper
3. The names "parententity" and "parentmapper" are underscored
also improved the message with the "neither comparator nor instruentedattribute...."
to include the classname + attribute name
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.
- modify inspection system:
1. raise a new exception for any case where the inspection
context can't be returned. this supersedes the "not mapped"
errors.
2. don't configure mappers on a mapper inspection. this allows
the inspectors to be used during mapper config time. instead,
the mapper configures on "with_polymorphic_selectable" now,
which is needed for all queries
- add a bunch of new "is_XYZ" attributes to inspectors
- finish making the name change of "compile" -> "configure", for some reason
this was only done partially
session.begin_nested() will now only expire
those objects that had net changes within the
scope of that transaction, that is objects which
were dirty or were modified on a flush. This
allows the typical use case for begin_nested(),
that of altering a small subset of objects, to
leave in place the data from the larger enclosing
set of objects that weren't modified in
that sub-transaction. [ticket:2452]
- inline the "register_newly_XYZ" functions to operate
upon collections to reduce method calls