Looks like this almost-sorta works:
class TagMixin(object): @declared_attr def TagClass(cls): class Tag(BaseModel): __tablename__ = "tag_%s" % cls.__tablename__ id = Column(types.Integer, primary_key=True) time_created = Column(types.DateTime, default=datetime.now, nullable=False) row_id = Column(types.Integer, ForeignKey(cls.id), index=True) name = Column(types.String, nullable=False, index=True) # This part breaks with... sqlalchemy.exc.InvalidRequestError: Table 'tag_user' is already defined for this MetaData instance. # @declared_attr # def tags(cls): # return orm.relationship(cls.TagClass, backref='tagged') class User(BaseModel, TagMixin): __tablename__ = 'user' id = Column(types.Integer, primary_key=True) ... The appropriate tables do get generated on create_all(). But as soon as I touch the User.TagClass attribute, it barfs with the same error again: InvalidRequestError: Table 'tag_user' is already defined for this MetaData instance. Specify 'extend_existing=True' to redefine options and columns on an existing Table object. -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalchemy@googlegroups.com. To unsubscribe from this group, send email to sqlalchemy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en.