oracle 中 group by 加强
group by rollup(a,b)
=
group by a,b
+
group by a
+
group by null
1 SQL> select deptno,job,sum(sal) 2 2 from emp 3 3 group by rollup(deptno,job); 4 5 DEPTNO JOB SUM(SAL) 6 ------ --------- ---------- 7 2000 8 2000 9 10 CLERK 1400 10 10 MANAGER 2450 11 10 PRESIDENT 5000 12 10 8850 13 20 CLERK 800 14 20 ANALYST 3000 15 20 MANAGER 2975 16 20 6775 17 30 CLERK 950 18 30 MANAGER 2850 19 30 SALESMAN 5600 20 30 9400 21 27025 22 23 15 rows selected