python - 尝试设置一对多关系时获取 sqlalchemy.exc.InvalidRequestError
问题描述
我有 2 个表,我试图用这种关系设置,但是当我尝试运行应用程序时,我得到:
sqlalchemy.exc.InvalidRequestError:一个或多个映射器无法初始化 - 无法继续初始化其他映射器。
class Items(Base):
__tablename__ = 'Item'
ID_ITEM = Column(Integer, primary_key=True)
NAME = Column(String(80, 'SQL_Latin1_General_CP1_CI_AS'), nullable=False)
addresses = relationship('Unit', backref='items', lazy=True)
class Unit(Base):
__tablename__ = 'Units'
ID_UNIT = Column(Integer, primary_key=True)
VALUE = Column(Numeric(12, 2), nullable=False)
item_id = Column(Integer, ForeignKey('item.id'), nullable=False)
我在这里做错了什么?
解决方案
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