//创建视图
create view empno(ename,job,hiredate)
as
select ename,job,hiredate from emp;
create view empno as select * from emp;
//删除视图
drop view empno;
//创建视图并且能够替换掉视图
create or replace 视图名称 as 子查询
//更新视图
with check option:不能更新视图的创建条件
create view empno(ename,job,hiredate)
as
select ename,job,hiredate from emp
with check option;
//视图只读
with read only：创建的视图只读
create view empno(ename,job,hiredate)
as
select ename,job,hiredate from emp
with read only;
