Mysql视图

创建与使用视图（view)

create view 视图名 as 查询语句(select * from student);

在student创建一个视图，包含学生的姓名、课程名和成绩
create view student_view2(sname,cname,grade) as select sname,cname,grade from student s,course c,sc where s.sno=sc.sno and c.cno=sc.cno;

删除视图（只能删除视图定义不能删除数据）

drop view if exists view_name;

查看视图定义

describe 视图名称;
show table status like'视图名';
show create view 视图名;
select * from information_schema.views where table_name= 视图名;

修改视图定义

修改视图的列名为（姓名、选修课、成绩）
create or replace view view_name as select sname,cname,grade from student s,course c,sc where s.sno=sc.sno and c.cno=sc.cno;

把列的名称再改为sname,cname,grade
alter view student_view2(sname,cname,grade) as select sname,cname,grade from student s,course c,sc where s.sno=sc.sno and c.cno=sc.cno;

更新视图数据

update view_name set sno='123',sname='张三',ssex='男',sbirth='1997-02-09';