MySQL如何使用视图插入修改删除数据

create database stu;
use stu;

create table student(
sid char(4) primary key,
sname varchar(20) not null,
sex enum('男','女'),
birth date,
grade year,
department enum('信息工程系','化学工程系','机械电子系') default '信息工程系',
addr varchar(50)
)charset=utf8mb4;

create table course(
cno char(2) primary key,
cname varchar(20) not null,
start int,
credit float
)charset=utf8mb4;

create table  score(
scid int primary key auto_increment ,
sid char(4),
cno char(2),
result float  check(result >= 0 and result <= 100)
)charset=utf8mb4;

create view  v1
as 
select sid,sname,sex,department,year(now())-year(birth) age
from student where department='化学工程系';

create view  v2
as 
select sid,sname,sex,department
from student where department='化学工程系';

create view v3
as 
select student.sid,sname,course.cno,cname,result
from student,score,course
where student.sid=score.sid and course.cno=score.cno;

insert v1(sid,sname,sex,department)values('8888','张敏敏','女','信息工程系');

insert v2(sid,sname,sex,department)values('8888','张敏敏','女','信息工程系');

insert v3 values('8888','张敏敏','01','大学英语',90);

insert v3(cno,cname) values('55','人工智能');

create  view v4
as
select sid,cno,result
from score
where result>=70 ;

create  view v5
as
select sid,cno,result
from v4
where result<=90 with local check option ;

create  view v6
as
select sid,cno,result
from v4
where result<=90 with cascaded check option ;

insert v4 values('0404','01',60);
insert v4 values('0404','02',80);

insert v5 values('0405','01',60);
insert v5 values('0405','02',95);
insert v5 values('0405','03',80);

insert v6 values('0406','01',60);
insert v6 values('0406','02',95);
insert v6 values('0406','03',80);

update v1 set sid='6688' where sid='8888';

delete from v2 where sid=‘8888';

create or replace view  v2
as 
select sid,sname,sex,department
from student;
update v2 set sid='6688' where sid='8888';
delete from v2 where sid='6688';