Question

我正在使用union all来组合两个select语句的结果。我正在尝试按date_requested列对结果进行分组。如果日期相同，我需要将两个查询合并为一行。现在，它在同一个日期保留两行。这是因为tracking_id列在两行之间是不同的。由于我并不担心tracking_id，我怎么绕过它并将它们组合起来呢？感谢。

(select trv.requested_date, trv.requested_status
from  tbl_trackvalue as trv ,tbl_tracking as t , tbl_offers as off , tblusers as usr
where t.id=trv.tracking_id  and off.id=t.offer_id and  usr.id=trv.tr_user_id and usr.id='1454' 
and trv.payment_status='pending' and trv.requested_status='declined'  group by trv.tr_user_id, trv.requested_date order by trv.requested_date asc )
union all 
(select mlc.requested_date, mlc.requested_status
from  tbl_trackvalue as trv ,tbl_tracking as t , tbl_offers as off , tblusers as usr, tbl_mailchimp_trackvalue as mlc
where trv.tracking_id=mlc.tracking_id  and off.id=t.offer_id and  usr.id=trv.tr_user_id and usr.id='1454' 
and mlc.payment_status='pending' and mlc.requested_status='declined'  group by trv.tr_user_id, mlc.requested_date order by mlc.requested_date asc )

更新代码：

select requested_date, requested_status
from (select trv.requested_date as requested_date, trv.requested_status as requested_status
        from  tbl_trackvalue as trv ,tbl_tracking as trk , tbl_offers as off , tblusers as usr
        where trk.id=trv.tracking_id  and off.id=trk.offer_id and  usr.id=trv.tr_user_id and usr.id='1454' 
        and trv.payment_status='pending' and trv.requested_status='declined'  group by trv.requested_date asc 
        union all
        select mlc.requested_date as requested date, mlc.requested_status as requested_status
        from  tbl_trackvalue as trv ,tbl_tracking as trk , tbl_offers as off , tblusers as usr, tbl_mailchimp_trackvalue as mlc
        where trv.tracking_id=mlc.tracking_id  and off.id=trk.offer_id and  usr.id=trv.tr_user_id and usr.id='1454' 
        and mlc.payment_status='pending' and mlc.requested_status='declined'  group by mlc.requested_date asc ) t 
group by requested_date

UDPATE II：我从选择中删除了别名，似乎修复了语法错误。我会做更多测试，以确保它适用于各种情况。谢谢您的帮助。我不知道你不能为你的选择使用别名。

Answer 1

从子查询中删除tracking_id并使用union：

(select trv.requested_date, trv.requested_status
from  tbl_trackvalue as trv, tbl_tracking as t , tbl_offers as off , tblusers as usr
where t.id=trv.tracking_id  and off.id=t.offer_id and  usr.id=trv.tr_user_id and usr.id='1454' 
and trv.payment_status='pending' and trv.requested_status='declined'  group by trv.tr_user_id, trv.requested_date order by trv.requested_date asc )
union
(select mlc.requested_date, mlc.requested_status
from  tbl_trackvalue as trv ,tbl_tracking as t , tbl_offers as off , tblusers as usr, tbl_mailchimp_trackvalue as mlc
where trv.tracking_id=mlc.tracking_id  and off.id=t.offer_id and  usr.id=trv.tr_user_id and usr.id='1454' 
and mlc.payment_status='pending' and mlc.requested_status='declined'  group by trv.tr_user_id, mlc.requested_date order by mlc.requested_date asc )

Answer 2

如果除了tracking_id之外的行完全相同，只需将其从列表中删除，然后使用UNION代替UNION ALL。如果您还有其他差异，则可能希望在最终结果中使用GROUP BY，以便可以对其他不同的值使用聚合函数。

当某些列具有不同的值时，将union all的结果合并为一行

2 个答案: