Question

我有一个表table1 从那我需要显示基于最高计数的前5个操作系统我需要将它们分组在三个操作系统os，device，model

上

当我在查询下执行时，我没有得到任何结果。在下面的查询中有什么问题？

SELECT * FROM
     (SELECT distinct os, count,
     DENSE_RANK () OVER (PARTITION BY os ORDER BY count DESC)rn
     FROM (Select os ,device,model,SUM(cal_count) as count
     from table1
     group by os,device,model)b ) a
     WHERE a.rn = 5
     ;

Answer 1

我会写这样的查询：

select t.*
from (select os, device, model, SUM(cal_count) as cnt,
             dense_rank() over (partition by os order by sum(cal_count) desc) as seqnum
      from table1
      group by os, device, model
     ) t
where seqnum <= 5;

据我了解你的查询，它只返回每组的第5行。也许存在某种错误。

没有从hive中的组中获取前n个记录的结果

1 个答案: