Question

我想从tblTasks（JobID，ItemName，ContentTypeID）中选择第二高的值

这就是我的意思。我打赌它可以做得更容易，但我不知道如何。

SELECT Max(JobID)    AS maxjobid,
       Max(ItemName) AS maxitemname,
       ContentTypeID
FROM   
      (SELECT JobID, ItemName, ContentTypeID
      FROM tblTasks Ta
      WHERE JobID NOT IN
            (SELECT MAX(JobID)
            FROM tblTasks Tb
            GROUP BY ContentTypeID)
            ) secmax

     GROUP BY secmax.ContentTypeID

Answer 1

我猜你想要这样的东西。

SELECT  JobID AS maxjobid,
        ItemName AS maxitemname,
        ContentTypeID
FROM    (SELECT JobID,
                ItemName,
                ContentTypeID,
                ROW_NUMBER() OVER (PARTITION BY ContentTypeID ORDER BY JobID DESC) Rn
         FROM   tblTasks Ta

        ) t
WHERE Rn = 2

这将为每个ContentTypeID提供第二高的JobID记录

Answer 2

我建议DENSE_RANK()，如果你想要第二个JobID：

SELECT tb.*
FROM (SELECT tb.*, DENSE_RANK() OVER (ORDER BY JobID DESC) as seqnum
      FROM tblTasks Tb
     ) tb
WHERE seqnum = 2;

如果没有重复项，则OFFSET / FETCH会更容易：

SELECT tb.*
from tblTasks
ORDER BY JobId
OFFSET 1
FETCH FIRST 1 ROW ONLY;

Answer 3

您可以使用以下语法：

{{1}}

Answer 4

SELECT * FROM tblTasks ORDER BY col DESC LIMIT 1, 1

选择第二个MAX值

4 个答案: