A use case has been identified for __table_cls__, which was
added in 1.0 just for the purpose of test fixtures. Add this to
public API and ensure the target use case (conditional table generation)
stays supported.
Change-Id: I87be5bcb72205cab89871fa586663bf147450995
Fixes: #4082
A warning is emitted if a subclass attempts to override an attribute
that was declared on a superclass using ``@declared_attr.cascading``
that the overridden attribute will be ignored. This use
case cannot be fully supported down to further subclasses without more
complex development efforts, so for consistency the "cascading" is
honored all the way down regardless of overriding attributes.
A warning is emitted if the ``@declared_attr.cascading`` attribute is
used with a special declarative name such as ``__tablename__``, as this
has no effect.
Ensure that documenation refers to the current inconsistency that
__tablename__ can be overridden by subclasses however
@declared_attr.cascading cannot.
Fixes: #4091Fixes: #4092
Change-Id: I3aecdb2f99d408e404a1223f5ad86ae3c7fdf036
The attributeimpl for a deferred_expression does not
support a scalar loader, add new configurability so that
the impl can have this flag turned off. Document
that the with_expression() system currently does not
offer any deferred loading.
To eliminate confusion over "deferred", which refers to
lazy loading of column attributes, and "with_expression",
which refers to an attribute that is explicitly at
query time only, rename deferred_expression to query_expression.
Change-Id: I07c4a050ed68c79ccbde9492e9de1630b7470d74
Added a new feature :func:`.orm.with_expression` that allows an ad-hoc
SQL expression to be added to a specific entity in a query at result
time. This is an alternative to the SQL expression being delivered as
a separate element in the result tuple.
Change-Id: Id8c479f7489fb02e09427837c59d1eabb2a6c014
Fixes: #3058
Added a new style of mapper-level inheritance loading
"polymorphic selectin". This style of loading
emits queries for each subclass in an inheritance
hierarchy subsequent to the load of the base
object type, using IN to specify the desired
primary key values.
Fixes: #3948
Change-Id: I59e071c6142354a3f95730046e3dcdfc0e2c4de5
is not supported.
Change-Id: I3724fea3f2d508210e35827eb1ea17f5e334da19
Fixes: #3673
(cherry picked from commit fcaf17766fdd22e67407e432f7666d63439d7a39)
(cherry picked from commit 8cce3beef7)
Added new flag :paramref:`.Session.enable_baked_queries` to the
:class:`.Session` to allow baked queries to be disabled
session-wide, reducing memory use. Also added new :class:`.Bakery`
wrapper so that the bakery returned by :paramref:`.BakedQuery.bakery`
can be inspected.
Change-Id: I5657af7a99d2b24c89d6aee1343f432728e3f807
remarkably, the examples for concrete and single were still
using classical mappings. Ensure all three examples use
modern declarative patterns, each illustrate the identical set
of query operations. Use back_populates, flat=True for joins,
etc. ensure flake8 linting, correct links and add a link back
from newly reworked inheritance documentation.
Change-Id: I8465a9badbb0eda804f457ccac599f051ee3c27c
The inheritance documentation is confused, disorganized, and out
of date. Reorganize and clarify, in particular in preparation
for new inheritance features.
Change-Id: Ibe6a35b4b0432bad866a6afb0598b2cf1b509f10
Adding a new kind of relationship loader that is
a cross between the "immediateload" and the "subquery"
eager loader, using an IN criteria to load related items
in bulk immediately after the lead query result is loaded.
Change-Id: If13713fba9b465865aef8fd50b5b6b977fe3ef7d
Fixes: #3944
The ``lazy="select"`` loader strategy now makes used of the
:class:`.BakedQuery` query caching system in all cases. This
removes most overhead of generating a :class:`.Query` object and
running it into a :func:`.select` and then string SQL statement from
the process of lazy-loading related collections and objects. The
"baked" lazy loader has also been improved such that it can now
cache in most cases where query load options are used.
Change-Id: Ic96792fffaa045ae9aa0a4657d6d29235d3efb85
Fixes: #3954
The :meth:`.Query.update` method can now accommodate both
hybrid attributes as well as composite attributes as a source
of the key to be placed in the SET clause. For hybrids, an
additional decorator :meth:`.hybrid_property.update_expression`
is supplied for which the user supplies a tuple-returning function.
Change-Id: I15e97b02381d553f30b3301308155e19128d2cfb
Fixes: #3229
The :func:`.attributes.flag_modified` function now raises
:class:`.InvalidRequestError` if the named attribute key is not
present within the object, as this is assumed to be present
in the flush process. To mark an object "dirty" for a flush
without referring to any specific attribute, the
:func:`.attributes.flag_dirty` function may be used.
Change-Id: I6c64e4d253c239e38632f38c27bb16e68fe8dfbe
Fixes: #3753
really of general use. This extension is there only
for those who really want it based on observed performance
characteristics.
Change-Id: I2f612f26fdef4ddbeb1158ab1b344fad7083b11c
This example doesn't work with 'back_populates' because 'parent_associations' and 'child_associations' are not defined in Parent and Child classes respectively.
Alternatively, we could create 'parent_associations' and 'child_associations' into the classes.
Mike Bayer