Question

如何创建仅为已登录用户存储数据的视图：这不起作用：SYS关系上不允许查询重写“

CREATE MATERIALIZED VIEW UserPerspective 
ENABLE QUERY REWRITE AS
      SELECT * FROM EMP e, DEPT d, Salgrade s
      WHERE e.DEPTNO = d.DEPTNO
        AND e.ENAME like (SELECT User FROM Dual)
        AND e.Sal BETWEEN s.Losal AND s.Hisal
;

看起来我无法在视图中使用（SELECT User FROM Dual）...如何正确执行：

AND e.ENAME like (SELECT User FROM Dual)

Answer 1

您可以在视图中引用USER，如下所示（请注意，删除Salgrade因为我没有该表。）：

CREATE VIEW V AS
SELECT e.EMPNO, e.ENAME, e.JOB, e.MGR, e.HIREDATE
   , e.SAL, e.COMM, e.DEPTNO, d.DNAME, d.LOC
FROM EMP e
INNER JOIN DEPT d ON e.DEPTNO = d.DEPTNO
WHERE e.ENAME = USER;

在物化视图中喜欢这样：

CREATE MATERIALIZED VIEW MV AS
SELECT e.EMPNO, e.ENAME, e.JOB, e.MGR, e.HIREDATE
   , e.SAL, e.COMM, e.DEPTNO, d.DNAME, d.LOC
FROM EMP e
INNER JOIN DEPT d ON e.DEPTNO = d.DEPTNO
WHERE e.ENAME = USER;

但是，在启用了查询重写的物化视图中，您无法引用USER：

CREATE MATERIALIZED VIEW MVEQR
ENABLE QUERY REWRITE AS
SELECT e.EMPNO, e.ENAME, e.JOB, e.MGR, e.HIREDATE
   , e.SAL, e.COMM, e.DEPTNO, d.DNAME, d.LOC
FROM EMP e
INNER JOIN DEPT d ON e.DEPTNO = d.DEPTNO
WHERE e.ENAME = USER;

<强> ORA-30353: expression not supported for query rewrite

原因： select子句引用了UID，USER，ROWNUM，SYSDATE，CURRENT_TIMESTAMP，MAXVALUE，序列号，绑定变量，相关变量，设置结果，触发器返回变量，并行表队列列，集合迭代器等。

  操作：删除有问题的表达式或禁用实体化视图上的REWRITE选项。

以下是否能满足您的需求？

CREATE MATERIALIZED VIEW MV_II
ENABLE QUERY REWRITE AS
SELECT e.EMPNO, e.ENAME, e.JOB, e.MGR, e.HIREDATE
   , e.SAL, e.COMM, e.DEPTNO, d.DNAME, d.LOC
FROM EMP e
INNER JOIN DEPT d ON e.DEPTNO = d.DEPTNO;

CREATE VIEW V_II AS
SELECT EMPNO, ENAME, JOB, MGR, HIREDATE
   , SAL, COMM, DEPTNO, DNAME, LOC
FROM MV_II
WHERE ENAME = USER;

Oracle - 如何使用用户个性化数据创建视图

1 个答案: