Question

您好我想要从下面的查询中获得前三个总和（工资）而不重复。我们不能使用rownum，因为它会给重复。有人可以帮我吗？

SELECT d.dname, SUM(e.sal)
FROM emp e ,dept d
WHERE e.deptno = d.deptno
GROUP BY d.dname;

Answer 1

   select dname,sum(distinct sal) from 
   (SELECT d.dname dname, sal,
    dense_rank() over (partition by e.deptno order by sal desc) rn 
    FROM emp e,dept d WHERE e.deptno = d.deptno) where rn<=3 group by dname;

在内部查询中我查询了dname，sal以及使用dense_rank（）函数我已经按照顺序给了deptno明智的工资行号

例如：

dname  sal  rn
.....  ...  ...
acc    5000  1
acc    3000  2
acc    3000  2
acc    2000  3
bcc    4500  1
bcc    3000  2 .....etc

在外部我只是使用不同的关键字

Answer 2

您可以尝试以下查询：

Select
  Agg_Sal.Dname, 
  Agg_Sal.Total_Sal,
  Rank() Over (Partition By Dname Order By Total_Sal Desc) Rank
From 
  (Select 
    D.Dname Dname, 
    Sum(Sal) As Total_Sal 
  From 
    Emp E, Dept D
  Where
    E.Deptno = D.Deptno
  Group By
    D.Dname) Agg_Sal
Where 
  Rank <= 3
Order By 
  Rank

类似于Here

上的最后一个例子

Answer 3

如果按工资降序订购，则rownum应该有效：

select *
  from (select d.dname, sum(e.sal)
          from emp e, dept d
         where e.deptno = d.deptno
         group by d.dname
         order by 2 desc)
 where rownum <= 3

Answer 4

在外部查询中也使用distinct函数以避免重复的总和。

    select distinct(a.sumsal),a.dname
        from (select d.dname, sum(e.sal)
                   from emp e, dept d
                   where e.deptno = d.deptno
                   group by d.dname
                   order by 2 desc) a
     where rownum <= 3;

SQL查询 - 前3个总和（sal）

4 个答案: