//增加 insert into stu set name='zhangsan',age=14,gender='nan'; insert into stu ( gender,age,name)values('nv',25,'gouzi'); //更新 update stu set gender='man' where name='gouzi'; //删去 delete from stu where stu_id=2; //查询 select * from stu; //查询 限制只查前3条 select * from stu limit 3 //查询 限制只查后3条 select * from stu limit 3 //查询 按stu_id 倒序排序 select * from stu order by stu_id desc