文件名称:在子查询中使用ALL操作符-SQL语言基础
文件大小:5.26MB
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更新时间:2024-05-15 13:25:03
SQL 基础
在子查询中使用ALL操作符
*
EMPNO ENAME JOB
--------- ---------- ---------
7839 KING PRESIDENT
7566 JONES MANAGER
7902 FORD ANALYST
7788 SCOTT ANALYST
SQL> SELECT empno, ename, job
2 FROM emp
3 WHERE sal > ALL
4 (SELECT avg(sal)
5 FROM emp
6 GROUP BY deptno);
2916.6667
2175
1566.6667
*
SELECT empno, ename, job FROM emp WHERE sal > ALL
(SELECT avg(sal) FROM emp GROUP BY deptno);
Multiple-Row Subqueries (continued)
The ALL operator compares a value to every value returned by a subquery. The slide example displays employees whose salary is greater than the average salaries of all the departments. The highest average salary of a department is $2916.66, so the query returns those employees whose salary is greater than $2916.66.
>ALL means more than the maximum and