建立视图code
create view IS_Student(sno,sname,grade) as select student.sno,sname,grade from student,sc where student.sno = sc.sno and sdept = 'IS' and cno = '2' with check option
删除视图索引
drop view IS_student
it
视图之间的相互索引io
create view IS_s1(sname,grade) as select sno,grade from IS_student where grade > 90