Mysql外键练习

在创建从表create table staff(id int primary key auto_increment,empName varchar(20) not null,departNum int not null,empHobby varchar(20),enpAge int check(age>20 and age<50),foreign key (departNum) references department(id));

创建主表数据insert into department(departName,departAddtrss) values('HR','aaa');insert into department(departName,departAddtrss) values('设计','bbb');insert into department(departName,departAddtrss) values('编程','ccc');insert into department(departName,departAddtrss) values('美工','ddd');insert into department(departName,departAddtrss) values('特工','eee');

创建从表数据insert into staff(empName,departNum,empHobby,enpAge) values('张无忌',1,'爬山',23);insert into staff(empName,departNum,empHobby,enpAge) values('张三丰',2,'爬树',40);insert into staff(empName,departNum,empHobby,enpAge) values('赵敏',3,'跳舞',21);insert into staff(empName,departNum,empHobby,enpAge) values('东邪',4,'瞎搞',35);insert into staff(empName,departNum) values('张翠山',2);