SQL Server：拿一个表＆amp;列并排比较

Question

我正在访问我的一个表，它在单独的行的列中显示vchCategory（电子序列号＃）的数据（esn），但我想在同一行中看到它，我该怎么办？

我想显示vchEsn, dtTransactionDatetime, vchCategory1, vchCategory2

select *
from tblDailySalesRpt_History s
where vchEsn in (select vchEsn
                 from tblDailySalesRpt_History s
                 where vchOrigSalesMonth = 'mar 2014'
                 group by s.vchEsn
                 having count(vchesn) >= 2)
order by 1

返回以下内容：

Answer 1

您可以使用PIVOT：

将多行中的数据一起收集到列中

select
  vchEsn, [Returns], [IW New Activation], [Deactivated]
from
  (select vchEsn, dtTransactionDateTime, vchCategory from tblDailySalesRpt_History) s
pivot
(
  MAX(dtTransactionDateTime)
  FOR vchCategory in ([Returns], [IW New Activation], [Deactivated])
) pvt
order by vchEsn

示例输出（DEMO）：

|             VCHESN |                      RETURNS |            IW NEW ACTIVATION |                  DEACTIVATED |
|--------------------|------------------------------|------------------------------|------------------------------|
| 256691413606894729 | March, 01 2014 11:34:24+0000 | March, 10 2014 16:20:51+0000 |                       (null) |
| 256691413607342471 | March, 12 2014 16:29:06+0000 | March, 17 2014 18:05:17+0000 |                       (null) |
| 256691413607372883 | March, 04 2014 10:46:18+0000 |                       (null) | March, 10 2014 20:01:33+0000 |