fields.py 文件源码

def remove(self, value):
        fd = self._field_descriptor
        if isinstance(value, SelectQuery):
            subquery = value.select(value.model_class._meta.primary_key)
            return (fd.through_model
                    .delete()
                    .where(
                        (fd.dest_fk << subquery) &
                        (fd.src_fk == self._instance.get_id()))
                    .execute())
        else:
            if not isinstance(value, (list, tuple)):
                value = [value]
            if not value:
                return
            return (fd.through_model
                    .delete()
                    .where(
                        (fd.dest_fk << self._id_list(value)) &
                        (fd.src_fk == self._instance.get_id()))
                    .execute())