Method test_external_columns

test/orm/test_froms.py:3660–3817

test querying mappings that reference external columns or selectables.

(self)

        clear_mappers()

    def test_external_columns(self):
        """test querying mappings that reference external columns or
        selectables."""

        users, Address, addresses, User = (
            self.tables.users,
            self.classes.Address,
            self.tables.addresses,
            self.classes.User,
        )

        self.mapper_registry.map_imperatively(
            User,
            users,
            properties={
                "concat": column_property(users.c.id * 2),
                "count": column_property(
                    select(func.count(addresses.c.id))
                    .where(
                        users.c.id == addresses.c.user_id,
                    )
                    .correlate(users)
                    .scalar_subquery()
                ),
            },
        )

        self.mapper_registry.map_imperatively(
            Address,
            addresses,
            properties={
                "user": relationship(
                    User,
                )
            },
        )

        sess = fixture_session()

        sess.query(Address).options(joinedload(Address.user)).all()

        eq_(
            sess.query(User).all(),
            [
                User(id=7, concat=14, count=1),
                User(id=8, concat=16, count=3),
                User(id=9, concat=18, count=1),
                User(id=10, concat=20, count=0),
            ],
        )

        address_result = [
            Address(id=1, user=User(id=7, concat=14, count=1)),
            Address(id=2, user=User(id=8, concat=16, count=3)),
            Address(id=3, user=User(id=8, concat=16, count=3)),
            Address(id=4, user=User(id=8, concat=16, count=3)),
            Address(id=5, user=User(id=9, concat=18, count=1)),
        ]