如何按日期分组dd / mm / yyyy格式？

Question

SELECT CONVERT(NVARCHAR(15), TransDate, 103)  AS TransDate, 
       Isnull(Sum(CONVERT(INT, Amount)), '0') AS Amount 
FROM   HMS_DiagnosisTransactions 
WHERE  TransDate BETWEEN '05/01/2015' AND '07/24/2015' 
GROUP  BY CONVERT(NVARCHAR(15), TransDate, 103) 
ORDER  BY CONVERT(NVARCHAR(15), TransDate, 103) 

它显示为

20/05/2015
20/06/2015
21/05/2015
22/07/2015

但我想要

20/05/2015
21/05/2015
20/06/2015
22/07/2015

Answer 1

在TransDate中加Group By（截断时间），然后您可以在Order By中使用它：

SELECT CONVERT(NVARCHAR(15), TransDate, 103)  AS TransDate, 
       Isnull(Sum(CONVERT(INT, Amount)), '0') AS Amount 
FROM   HMS_DiagnosisTransactions 
WHERE  TransDate BETWEEN '05/01/2015' AND '07/24/2015' 
GROUP  BY CONVERT(NVARCHAR(15), TransDate, 103), DATEADD(dd, DATEDIFF(dd, 0, TransDate), 0) 
ORDER BY DATEADD(dd, DATEDIFF(dd, 0, TransDate), 0) 

即使在SQL-Server 2005及更低版本中也是如此。 2008年推出了Date数据类型，它没有时间部分。然后你只需要把它投到Date：

SELECT CONVERT(NVARCHAR(15), TransDate, 103)  AS TransDate, 
       Isnull(Sum(CONVERT(INT, Amount)), '0') AS Amount 
FROM   HMS_DiagnosisTransactions 
WHERE  TransDate BETWEEN '05/01/2015' AND '07/24/2015' 
GROUP  BY CONVERT(NVARCHAR(15), TransDate, 103), CAST(TransDate as Date) 
ORDER  BY CAST(TransDate as Date) 

Answer 2

我假设分组实际上有一个目的，因此您需要使用分组值。将字符串转换回日期：

ORDER BY CONVERT(DATETIME, CONVERT(NVARCHAR(15), TransDate, 103), 103)

Answer 3

也许您可以将年/月/日值声明为DATEPART，也可以将它们分组，同时在派生表中执行所有操作。然后只需重新查询它。

SELECT T.TransDate, T.Amount
FROM (
    SELECT CONVERT(NVARCHAR(15), TransDate, 103) AS TransDate
        , COALESCE(SUM(CONVERT(INT, Amount)), '0') AS Amount
        , DATEPART(DD, TransDate) AS DD
        , DATEPART(MM, TransDate) AS MM
        , DATEPART(YY, TransDate) AS YY
    FROM HMS_DiagnosisTransactions
    WHERE TransDate BETWEEN '05/01/2015' AND '07/24/2015'
    GROUP BY CONVERT(NVARCHAR(15), TransDate, 103)
        , DATEPART(DD, TransDate)
        , DATEPART(MM, TransDate)
        , DATEPART(YY, TransDate)
    ) AS T
ORDER BY T.YY, T.MM, T.DD;