oracle having

在 SQL 中增加 HAVING 子句原因是，WHERE 关键字无法与合计函数一起使用。

SQL> conn scott/tiger已连接。SQL> select deptno, count(deptno) from emp group by deptno;    DEPTNO COUNT(DEPTNO)---------- -------------        30             6        20             5        10             3SQL> select deptno, count(deptno) from emp group by deptno having(count(deptno)) > 5;    DEPTNO COUNT(DEPTNO)---------- -------------        30             6