Question

我正在尝试在表上执行聚合。但在某些情况下，它没有正确聚合。请找到以下输入。

表t1。

CHANNEL;VALUE;STATUS;ERROR_CODE;RND_TIMESTAMP;SESSION_CD;NAR;
-------------------------------------------------------------    
USD;4;12;;2-NOV-2015 11:00:00;;
USD;4;12;;2-NOV-2015 11:00:00;;
USD;2;12;;2-NOV-2015 11:00:00;;
USD;3;12;;2-NOV-2015 11:00:00;;

输出表t2

CHANNEL;VALUE;STATUS;ERROR_CODE;HOUR_TIMESTAMP;SESSION_CD;NAR;
--------------------------------------------------------------    
USD;5;12;;2-NOV-2015 11:00:00;;

查询：

select 
    channel, sum(value), 
    status, error_code, rnd_timestamp, session_cd, nar
from 
    t1
where 
    rnd_timestamp > (select max(hour_timestamp) from t2)
group by 
    channel, status, error_code, rnd_timestamp, session_cd, nar

为什么不考虑其他2行进行聚合。是因为group by中的某些列有null吗？如何解决这个问题？

输出必须是：

USD;13;12;;2-NOV-2015 11:00:00;;

Answer 1

为什么您认为您的查询存在问题？

通过将t2中的hour_timestamp切换为上午10点而不是上午11点，您的查询按预期工作：

with t1 as (select 'USD' channel, 4 value, 12 status, null error_code, to_date('02/11/2015 11:00:00', 'dd/mm/yyyy hh24:mi:ss') rnd_timestamp, null session_cd, null nar from dual union all
            select 'USD' channel, 4 value, 12 status, null error_code, to_date('02/11/2015 11:00:00', 'dd/mm/yyyy hh24:mi:ss') rnd_timestamp, null session_cd, null nar from dual union all
            select 'USD' channel, 2 value, 12 status, null error_code, to_date('02/11/2015 11:00:00', 'dd/mm/yyyy hh24:mi:ss') rnd_timestamp, null session_cd, null nar from dual union all
            select 'USD' channel, 3 value, 12 status, null error_code, to_date('02/11/2015 11:00:00', 'dd/mm/yyyy hh24:mi:ss') rnd_timestamp, null session_cd, null nar from dual),
     t2 as (select 'USD' channel, 5 value, 12 status, null error_code, to_date('02/11/2015 10:00:00', 'dd/mm/yyyy hh24:mi:ss') hour_timestamp, null session_cd, null nar from dual)
--- end of mimicking your tables t1 and t2 with data in; see SQL below:
select   channel,
         sum(value), 
         status,
         error_code,
         rnd_timestamp,
         session_cd,
         nar
from     t1
where    rnd_timestamp > (select max(hour_timestamp) from t2)
group by channel,
         status,
         error_code,
         rnd_timestamp,
         session_cd,
         nar;

CHANNEL SUM(VALUE)     STATUS ERROR_CODE RND_TIMESTAMP         SESSION_CD NAR
------- ---------- ---------- ---------- --------------------- ---------- ---
USD             13         12            02/11/2015 11:00:00

使用sql按问题分组

1 个答案: