Проверка 09.02.2025

venv/Lib/site-packages/sqlalchemy/orm/mapper.py

@@ -1,5 +1,5 @@
 # orm/mapper.py
-# Copyright (C) 2005-2024 the SQLAlchemy authors and contributors
+# Copyright (C) 2005-2025 the SQLAlchemy authors and contributors
 # <see AUTHORS file>
 #
 # This module is part of SQLAlchemy and is released under
@@ -296,6 +296,17 @@ class Mapper(
            particular primary key value. A "partial primary key" can occur if
            one has mapped to an OUTER JOIN, for example.
 
+           The :paramref:`.orm.Mapper.allow_partial_pks` parameter also
+           indicates to the ORM relationship lazy loader, when loading a
+           many-to-one related object, if a composite primary key that has
+           partial NULL values should result in an attempt to load from the
+           database, or if a load attempt is not necessary.
+
+           .. versionadded:: 2.0.36 :paramref:`.orm.Mapper.allow_partial_pks`
+              is consulted by the relationship lazy loader strategy, such that
+              when set to False, a SELECT for a composite primary key that
+              has partial NULL values will not be emitted.
+
         :param batch: Defaults to ``True``, indicating that save operations
            of multiple entities can be batched together for efficiency.
            Setting to False indicates
@@ -318,7 +329,7 @@ class Mapper(
 
                 class User(Base):
                     __table__ = user_table
-                    __mapper_args__ = {'column_prefix':'_'}
+                    __mapper_args__ = {"column_prefix": "_"}
 
            The above mapping will assign the ``user_id``, ``user_name``, and
            ``password`` columns to attributes named ``_user_id``,
@@ -442,7 +453,7 @@ class Mapper(
           mapping of the class to an alternate selectable, for loading
           only.
 
-         .. seealso::
+          .. seealso::
 
             :ref:`relationship_aliased_class` - the new pattern that removes
             the need for the :paramref:`_orm.Mapper.non_primary` flag.
@@ -534,14 +545,14 @@ class Mapper(
           base-most mapped :class:`.Table`::
 
             class Employee(Base):
-                __tablename__ = 'employee'
+                __tablename__ = "employee"
 
                 id: Mapped[int] = mapped_column(primary_key=True)
                 discriminator: Mapped[str] = mapped_column(String(50))
 
                 __mapper_args__ = {
-                    "polymorphic_on":discriminator,
-                    "polymorphic_identity":"employee"
+                    "polymorphic_on": discriminator,
+                    "polymorphic_identity": "employee",
                 }
 
           It may also be specified
@@ -550,17 +561,18 @@ class Mapper(
           approach::
 
             class Employee(Base):
-                __tablename__ = 'employee'
+                __tablename__ = "employee"
 
                 id: Mapped[int] = mapped_column(primary_key=True)
                 discriminator: Mapped[str] = mapped_column(String(50))
 
                 __mapper_args__ = {
-                    "polymorphic_on":case(
+                    "polymorphic_on": case(
                         (discriminator == "EN", "engineer"),
                         (discriminator == "MA", "manager"),
-                        else_="employee"),
-                    "polymorphic_identity":"employee"
+                        else_="employee",
+                    ),
+                    "polymorphic_identity": "employee",
                 }
 
           It may also refer to any attribute using its string name,
@@ -568,14 +580,14 @@ class Mapper(
           configurations::
 
                 class Employee(Base):
-                    __tablename__ = 'employee'
+                    __tablename__ = "employee"
 
                     id: Mapped[int] = mapped_column(primary_key=True)
                     discriminator: Mapped[str]
 
                     __mapper_args__ = {
                         "polymorphic_on": "discriminator",
-                        "polymorphic_identity": "employee"
+                        "polymorphic_identity": "employee",
                     }
 
           When setting ``polymorphic_on`` to reference an
@@ -592,6 +604,7 @@ class Mapper(
                 from sqlalchemy import event
                 from sqlalchemy.orm import object_mapper
 
+
                 @event.listens_for(Employee, "init", propagate=True)
                 def set_identity(instance, *arg, **kw):
                     mapper = object_mapper(instance)
@@ -3248,14 +3261,9 @@ class Mapper(
         The resulting structure is a dictionary of columns mapped
         to lists of equivalent columns, e.g.::
 
-            {
-                tablea.col1:
-                    {tableb.col1, tablec.col1},
-                tablea.col2:
-                    {tabled.col2}
-            }
+            {tablea.col1: {tableb.col1, tablec.col1}, tablea.col2: {tabled.col2}}
 
-        """
+        """  # noqa: E501
         result: _EquivalentColumnMap = {}
 
         def visit_binary(binary):
@@ -3728,14 +3736,15 @@ class Mapper(
 
         given::
 
-            class A:
-                ...
+            class A: ...
+
 
             class B(A):
                 __mapper_args__ = {"polymorphic_load": "selectin"}
 
-            class C(B):
-                ...
+
+            class C(B): ...
+
 
             class D(B):
                 __mapper_args__ = {"polymorphic_load": "selectin"}
@@ -3805,6 +3814,7 @@ class Mapper(
         this subclass as a SELECT with IN.
 
         """
+
         strategy_options = util.preloaded.orm_strategy_options
 
         assert self.inherits
@@ -3828,7 +3838,7 @@ class Mapper(
             classes_to_include.add(m)
             m = m.inherits
 
-        for prop in self.attrs:
+        for prop in self.column_attrs + self.relationships:
             # skip prop keys that are not instrumented on the mapped class.
             # this is primarily the "_sa_polymorphic_on" property that gets
             # created for an ad-hoc polymorphic_on SQL expression, issue #8704