问:Oracle的EMP表,查询每个部门工资前三名的员工信息,如何写??
解答:(通用sql)
Oracle查询:(利用分区功能)
解答:(通用sql)
select deptno, ename, sal
from emp e1
where
(
select count(1)
from emp e2
where e2.deptno=e1.deptno and e2.sal>=e1.sal
) <=3 /*这里的数值表示你想取前几名*/
order by deptno, sal desc;
Oracle查询:(利用分区功能)
select * from
(select deptno,ename,sal,row_number() over (partition by deptno
order by sal desc) rn
from emp)
where rn<3;