Question

我有这样的查询：

SELECT TOP 5
    CONVERT(varchar(15), CAST(Pout AS time), 100) AS 'OUT',
    CONVERT(varchar(15), CAST(pIn AS time), 100) AS 'IN',
    DATEDIFF(MINUTE, CONVERT(varchar(5), Pout, 108), CONVERT(varchar(5), pIn, 108)) AS [Total Used]
FROM 
    loginfo
WHERE 
    empid = 1001
    AND CONVERT(date, pDate) = '28/Nov/2016 2:45:00 PM'
    AND pOut IS NOT NULL
ORDER BY 
    pOut

此查询工作正常，但我不想显示前5条记录，我需要显示最近5条记录，我的意思是最近5条记录，但我不能ORDER BY pout DESC，因为我想要以正确的格式显示报告，但我只需要显示我的交易的最后5条记录而不使用降序

示例如果我有记录10事务，我想只显示格式正确的最后5条记录

Answer 1

改为使用ROW_NUMBER()：

SELECT * FROM (
    SELECT
          CONVERT(varchar(15), CAST(Pout AS time), 100) AS [OUT],
          CONVERT(varchar(15), CAST(pIn AS time), 100) AS [IN],
          DATEDIFF(MINUTE, CONVERT(varchar(5), Pout, 108),     
          CONVERT(varchar(5), pIn, 108)) AS [Total Used],
          ROW_NUMBER() OVER(ORDER BY pOut DESC) as rnk
    FROM loginfo
    WHERE empid = 1001
      AND CONVERT(date, pDate) = '28/Nov/2016 2:45:00 PM'
      AND pOut IS NOT NULL) p
WHERE p.rnk <= 5
ORDER BY What_Ever_You_Want

或者，或者，使用派生表：

SELECT * FROM (Your Current Query)
ORDER BY pOut ;

Answer 2

您可以使用ROW_NUMBER，但您还必须使用DESC。

; WITH CTE AS
(
  SELECT
  CONVERT(varchar(15), CAST(Pout AS time), 100) AS 'OUT',
  CONVERT(varchar(15), CAST(pIn AS time), 100) AS 'IN',
  DATEDIFF(MINUTE, CONVERT(varchar(5), Pout, 108), CONVERT(varchar(5), pIn, 108)) AS [Total Used],
  ROW_NUMBER() OVER(ORDER BY pOut DESC) AS RN
  FROM loginfo
  WHERE empid = 1001
  AND CONVERT(date, pDate) = '28/Nov/2016 2:45:00 PM'
  AND pOut IS NOT NULL
) SELECT * FROM CTE 
WHERE RN BETWEEN 1 AND 5
ORDER BY OUT

在不使用desc

2 个答案: