SQLAlchemy：相同类型的多个foreignKey

Question

我有一个类似的课程：

class Component(Base):
    __tablename__ = 'components'

    id = Column(Integer, primary_key=True)
    .
    .
    .
    .
    alternate1_id = Column(Integer, foreignkey("components.id"), nullable=True)
    alternate2_id = Column(Integer, foreignkey("components.id"), nullable=True)
    alternate3_id = Column(Integer, foreignkey("components.id"), nullable=True)

    def __init__(self, catalog_number, component_type, manufacturer_pn, description):
            self.catalog_number = catalog_number
            self.component_type = component_type
            self.manufacturer_pn = manufacturer_pn
            self.description = description

    def __repr__(self):
            return "<Component('%s', '%s', '%s', '%s')>" % (self.catalog_number,
                                                            self.component_type,

alternate1,2和3是可选字段，指向当前实例的替代组件。

如何创建三个关系，每个关系指向每个id？

Answer 1

请参阅handling multiple join paths中有关foreign_keys的{​​{1}}参数的示例。