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Sqlalchemy 的联级删除

作者:互联网

原文地址

class Parent(db.Model):
    __tablename__ = 'parent'
    id = Column(Integer, primary_key=True)
    name = Column(String(20))


class Child(db.Model):
    __tablename__ = 'child'
    id = Column(Integer, primary_key=True)
    name = Column(String(20))

    parent_id = Column(Integer, ForeignKey('parent.id'))
    parent = relationship("Parent", backref=backref("child"))

    ###  只删除父级,子不影响
    # 1. parent_id = Column(Integer, ForeignKey('parent.id', ondelete="CASCADE"))
    #    parent = relationship("Parent", backref=backref("child", passive_deletes=True))

    ###  子级跟随删除
    # 2. parent = relationship("Parent", backref = backref("child", cascade="all, delete-orphan"))
    # 3. parent = relationship("Parent", backref = backref("child", cascade="all,delete"))

    ##  父级删除,子级不删除,外键更新为 null
    # 4. parent = relationship("Parent", backref = backref("child"))

 

标签:Sqlalchemy,删除,parent,Column,Parent,child,联级,backref,id
来源: https://blog.csdn.net/q389797999/article/details/113129605