#先建被关联的表,并保证被关联的字段唯一 再建被关联的表 #1 建立表关系: create table dep( id int primary key, name char(16), comment char(50) ); create table emp( id int primary key, name char(10), sex enum('male','female'), dep_id int, foreign key(dep_id) references dep(id) on delete cascade on update cascade ); #2 插入数据: 先插入被关联表记录 insert into dep values (1,'IT','技术能力有限部门'), (2,'销售','销售能力有限部门'), (3,'财务','花钱特别多部门'); #再往关联表插入记录 insert into emp values (1,'eddie','male',1), (2,'kevin','male',1), (3,'赵晓迪','female',3), (4,'iris','female',2); delete from emp where dep_id=1; #删除的时候先删除被关联的表数据 delete from dep where id=1; update dep set id=3333 where id =3;
4 foreign key 表关联
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转载自www.cnblogs.com/zhujing666/p/12312441.html
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