Question

当我像这样在蜂巢中使用嵌套选择时

Select 
a.month,
a.day,
sum(a.pv)/count(a.*) 
from 
(Select month,day, remote_addr,count(1) as pv 
from ods_weblog_detail group by remote_addr,month,day) as a;

它返回错误消息：“当前上下文不支持TOK_ALLCOLREF。”

但是当我分别选择a.month，a.day和sum（a.pv）/ count（a。*）时，像这样：

Select 
sum(a.pv)/count(a.*) 
from 
(Select month,day, remote_addr,count(*) as pv from ods_weblog_detail group by remote_addr,month,day) as a;

或此

：

Select 
a.month,a.day 
from 
(Select month,day, remote_addr,count(*) as pv 
from 
ods_weblog_detail 
group by remote_addr,month,day) as a;

两种说法都给了我正确的答案。 那么，为什么不能在一个语句中同时选择这三个（a.month，a.day和sum（a.pv）/ count（a。*））？非常感谢！！！

Answer 1

查询缺少group by。

Select 
a.month,
a.day,
sum(a.pv)/count(a.*) 
from (select month,day, remote_addr,count(1) as pv 
      from ods_weblog_detail 
      group by remote_addr,month,day
     ) a
group by a.month,a.day

查询也可以简化如下。

select month,day,remote_addr
,sum(count(*)) over(partition by month,day,remote_addr)/count(*) over(partition by month,day) as res
from ods_weblog_detail

错误消息：在hive2.3.3中使用嵌套选择时，“当前上下文不支持TOK_ALLCOLREF”

1 个答案: