Question

假设我有一个父表：FAMILY_MEMBER，每个都有unique ID个ID。

我还有FAMILY表mother_id，father_id和daughter_id，每个表都指向FAMILY_MEMBER行。

当我删除FAMILY行时，我希望数据库自动删除3 FAMILY_MEMBER个父行。这似乎与ON DELETE和ON UPDATE条款的目的完全相反。

Answer 1

create trigger t1
    after delete on FAMILY
        for each row
            BEGIN
            delete from family_member
                where id = old.mother_id;
            delete from family_member
                where id = old.fa=ther_id;
            delete from family_member
                where id = old.daughter_id;
            END

或者这个（您可以使用分隔符作为触发器和表的名称）：

create trigger `t1`
    after delete on `FAMILY`
        for each row
            BEGIN
            delete from family_member
                where id = old.mother_id;
            delete from family_member
                where id = old.fa=ther_id;
            delete from family_member
                where id = old.daughter_id;
            END

MySQL：删除CHILDREN行时删除PARENTS

1 个答案: