ORACLE_VIEW-白红宇

ORACLE_VIEW

阅读量：340 次

发布时间：2019-03-04

本文共 839 字，大约阅读时间需要 2 分钟。


   
   
   
GRANT权限以允许用户创建视图
   
GRANT CREATE VIEW TO SCOTT;
   
创建基本视图
   
CREATE OR REPLACE VIEW V1 AS SELECT * FROM EMP, SAL FROM EMP;
   
使用视图进行SELECT操作
   
SELECT * FROM V1;
   
创建另一个名称的视图
   
CREATE OR REPLACE VIEW V2(ID, NAME, SAL) AS SELECT EMPNO, ENAME, SAL FROM EMP;
   
查询V2视图并基于ID筛选
   
SELECT * FROM V2 WHERE ID=7369;
   
查询表结构信息
   
SELECT TABLE_NAME, COLUMN_NAME, UPDATABLE, INSERTABLE, DELETEABLE FROM TABLE WHERE TABLE_NAME='EMP';
   
添加视图数据
   
INSERT INTO V1 VALUES(1, 'TOM', 15);
   
创建只读视图
   
CREATE OR REPLACE VIEW V3 AS SELECT ENAME FROM EMP WITH READ ONLY;
   
创建带检查选项的视图
   
CREATE OR REPLACE VIEW V4 AS SELECT ENAME, SAL FROM EMP WHERE DEPTNO=20 WITH CHECK OPTION CONSTRAINT VM_CK;
   
创建复杂视图
   
CREATE OR REPLACE VIEW V4 AS SELECT D.DNAME, E.ENAME FROM EMP E JOIN DEPT D ON E.DEPTNO = D.DEPTNO GROUP BY DEPTNO;
   
查询V4视图
   
SELECT * FROM V4;