摘要:
1 --1.单独使用Group By子句:每个分组返回一条记录2 select a.division_id, sum(a.salary)3 from employees2 a4 group by a.division_id5 order by a.division_id运行结果:1 DIVISION_ID SUM(A.SALARY)2 1 BUS 16100003 2 OPE 13200004 3 SAL 49360005 4 SUP 10150001 --2.扩展子句Rollup: 每个分组返回一条小计,最后返回一条总计2 ... 阅读全文