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sqlalchemy 中关于一对一使用相同的column name,设置外键的方式

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sqlalchemy 中关于一对一使用相同的column name,设置外键的方式

I am mapping classes to existed MySQL tables . I need to relate to tables(one-to-one), but I’ve got a problem. Two tables have the column nid. Both fields are primary keys. I can not define foreign key without a primary key. And relation map is not applied to a primary key. My version is below.

class Node(base):
    __tablename__ = 'node'
    nid = Column(Integer, primary_key=True)
    vid = Column(Integer)
    uuid = Column(String(128))
    type = Column(String)

    field_data = relationship("NodeFieldData", order_by="NodeFieldData.nid", backref="node")

    def __repr__(self):
        return "" % (self.nid, self.vid, self.uuid, self.type)

class NodeFieldData(base):
    __tablename__ = 'node_field_data'
    nid = Column(Integer, primary_key=True)
    type = Column(String, nullable=False)
    title = Column(String, nullable=False)
    #nid = Column(Integer, ForeignKey('Node.nid'))

    def __repr__(self):
        return "" % (self.nid, self.vid, self.uuid, self.type)

解决方式
nid = Column(Integer, ForeignKey(Node.nid), primary_key=True)

base = declarative_base()
class Node(base):
    __tablename__ = 'node'
    nid = Column(Integer, primary_key=True)
    uuid = Column(String(128))
    vid = Column(Integer)
    type = Column(String)

    # Refferer.
    field_data = relationship('NodeFieldData', backref="node", uselist=False)

    def __repr__(self):
        return "" % (self.nid, self.uuid, self.vid, self.type, self.field_data.title)

class NodeFieldData(base):
    __tablename__ = 'node_field_data'
    nid = Column(Integer, ForeignKey(Node.nid), primary_key=True)
    #vid = Column(Integer, primary_key=True)
    title = Column(String, nullable=False)

    def __repr__(self):
        return "" % (self.nid, self.title)
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