Module « sqlalchemy.orm »

Fonction declarative_mixin - module sqlalchemy.orm

Signature de la fonction declarative_mixin

def declarative_mixin(cls) 

Description

declarative_mixin.__doc__

Mark a class as providing the feature of "declarative mixin".

    E.g.::

        from sqlalchemy.orm import declared_attr
        from sqlalchemy.orm import declarative_mixin

        @declarative_mixin
        class MyMixin:

            @declared_attr
            def __tablename__(cls):
                return cls.__name__.lower()

            __table_args__ = {'mysql_engine': 'InnoDB'}
            __mapper_args__= {'always_refresh': True}

            id =  Column(Integer, primary_key=True)

        class MyModel(MyMixin, Base):
            name = Column(String(1000))

    The :func:`_orm.declarative_mixin` decorator currently does not modify
    the given class in any way; it's current purpose is strictly to assist
    the :ref:`Mypy plugin <mypy_toplevel>` in being able to identify
    SQLAlchemy declarative mixin classes when no other context is present.

    .. versionadded:: 1.4.6

    .. seealso::

        :ref:`orm_mixins_toplevel`

        :ref:`mypy_declarative_mixins` - in the
        :ref:`Mypy plugin documentation <mypy_toplevel>`