Question

我找到了第一笔交易（分钟），但是当我添加“赢家”栏目时，我获得了他们的第一场胜利和第一场失利的一排。我只需要第一排，包括他们是赢还是输。我试过汇总获奖者列无济于事。如果可能的话，我宁愿不进行子查询。提前感谢您查看此内容。

SELECT 
MIN(dbo.ADT.Time) AS FirstShowWager, 
dbo.AD.Account,  dbo.AD.FirstName, 
dbo.AD.LastName, dbo.ADW.Winners  

FROM     
dbo.BLAH
WHERE       
(dbo.ADT.RunDate = CONVERT(DATETIME, '2014-04-12
00:00:00', 102)) AND (dbo.ADW.Pool = N'shw') 

GROUP BY
dbo.AD.Account, 
dbo.AD.FirstName,
dbo.AD.LastName,
dbo.AD.RunDate, 
dbo.ADW.Winners 

ORDER BY 
dbo.AD.Account

Answer 1

听起来你并不关心winners列的价值，通过对获胜者进行分组，您可以获得多行，一个用于null，其他用于非null值。如果你不关心他们赢得的金额，只是如果他们赢了或输了，你可以做这样的事情，

SELECT 
MIN(dbo.ADT.Time) AS FirstShowWager, 
dbo.AD.Account,  dbo.AD.FirstName, 
dbo.AD.LastName, CASE WHEN dbo.ADW.Winners IS NULL THEN 0 ELSE 1 END

FROM     
dbo.BLAH
WHERE       
(dbo.ADT.RunDate = CONVERT(DATETIME, '2014-04-12
00:00:00', 102)) AND (dbo.ADW.Pool = N'shw') 

GROUP BY
dbo.AD.Account, 
dbo.AD.FirstName,
dbo.AD.LastName,
dbo.AD.RunDate, 
dbo.ADW.Winners 

ORDER BY 
dbo.AD.Account

Answer 2

select sorted.* 
from 
(
    SELECT dbo.ADT.Time AS FirstShowWager, 
           dbo.AD.Account,  dbo.AD.FirstName, 
           dbo.AD.LastName, dbo.ADW.Winners,  
           ROW_NUMBER ( ) OVER (partition by dbo.AD.Account, 
                                             dbo.AD.FirstName,
                                             dbo.AD.LastName,
                                             dbo.AD.RunDate
                                    order by dbo.ADT.Time) as rowNum
      FROM dbo.AD
     WHERE dbo.ADT.RunDate = CONVERT(DATETIME, '2014-04-1200:00:00', 102) 
       AND dbo.ADW.Pool = N'shw'
) as sorted 
where rowNum = 1

ROW_NUMBER

Answer 3

通过

在select语句和组中添加此case语句而不是winners列

 Case ( winners is NULL then 'Lose' else 'Win' end )

Answer 4

通常这是通过派生表来完成的，该表选择您想要的记录，然后加入到所有分组字段的原始表中。

Answer 5

您可以在内部查询中找到MIN，然后通过ID将其加入到ADW表中，以获取它们是否为赢家。

SELECT b.*, ADW.winner 
FROM dbo.ADW ADW INNER JOIN (SELECT MIN(ADT.RunTime) AS FirstShowWager, 
                             AD.Account,  AD.FirstName, 
                             AD.Lastnamne, AD.ADID
                             FROM dbo.AD AD INNER JOIN dbo.ADT ADT AD.adid = ADT.ADID 
                             GROUP BY AD.Account, AD.Firstname, AD.Lastnamne, AD.ADID) b
    ON ADW.ADID = b.ADID

假设：之间有一个外键从ADT到AD表。从ADW到AD表。

如何找到min，SQL group by

5 个答案: