Question

我在SQL Server中有这个查询：

SELECT DISTINCT
D214.DESTIMATED,
D214.LINSEQNO,
H214.SHPID 
FROM IN_214_HDR H214
JOIN IN_214_DTL D214 ON H214.TRANNO = D214.TRANNO
WHERE H214.SHPID = 'NGB8264646'

它将返回此结果集

DESTIMATED                   LINSEQNO     SHPID
2014-08-24 00:00:00.000          1      NGB8264646
2014-09-09 00:00:00.000          2      NGB8264646
2014-09-09 00:00:00.000          3      NGB8264646
2014-09-23 00:00:00.000          4      NGB8264646

使用不同的H214.SHPID我会得到不同数量的行返回，它们都会有一个LINSEQNO = 1

DESTIMATED                   LINSEQNO     SHPID
2014-08-24 00:00:00.000          1      NGB8262321
2014-09-12 00:00:00.000          2      NGB8262321
2014-09-18 00:00:00.000          3      NGB8262321
2014-10-23 00:00:00.000          4      NGB8262321
2014-10-29 00:00:00.000          5      NGB8262321
2014-11-09 00:00:00.000          6      NGB8262321

我需要的是一个返回相同列的查询，但我只需要LINSEQ最大的行。所以每个人都需要这样的结果集......

DESTIMATED                   LINSEQNO     SHPID
2014-09-23 00:00:00.000          4      NGB8264646

和

DESTIMATED                   LINSEQNO     SHPID
2014-11-09 00:00:00.000          6      NGB8264646

LINSEQNO的最小值将为1，但最大值可以是任何＆gt; 1。

Answer 1

SELECT TOP 1 D214.DESTIMATED,
             D214.LINSEQNO,
             H214.SHPID 
FROM IN_214_HDR H214
JOIN IN_214_DTL D214 ON H214.TRANNO = D214.TRANNO
WHERE H214.SHPID = 'NGB8264646'
ORDER BY LINSEQNO DESC

Answer 2

使用窗口功能：

select DESTIMATED, LINSEQNO, SHPID
from (select D214.DESTIMATED, D214.LINSEQNO, H214.SHPID,
             row_number() over (partition by H214.SHPID order by D214.LINSEQNO desc) as seqnum
      from IN_214_HDR H214 joi
           IN_214_DTL D214
           on H214.TRANNO = D214.TRANNO
     ) t
where seqnum = 1;

获取值最大的行

2 个答案: