Question

我有一个包含许多ID的表，其中包含两个可能的“类型”，并且每个ID与“类型”相关联的日期很多。我想选择ID，“Type”A的最新日期和“Type”B的最接近日期，大于A类。

Sample Table        
ID  Type    Date
1   A   1/5/2013
1   A   1/10/2013
1   B   1/1/2013
2   A   2/10/2013
2   A   2/9/2013
2   B   2/15/2013
2   B   2/20/2013
3   A   3/15/2013
3   B   3/10/2013
3   B   3/20/2013

期望的结果

ID  Date A  Date B
2   2/10/2013   2/15/2013
3   3/15/2013   3/20/2013

ID 1保持关闭，因为它不满足条件B＆gt;最大（typeA）{1/10/13} ID 2等于max（typeA）{2/10/13 vs 2/9/13}，而Date B {2/15/13}大于Date A，并且是满足该条件的两个日期中最接近的日期。 ID 3仅等于大于日期A的条目和最接近的B条目{3/20/13}

我已经尝试了几次min，max和row / partition迭代，但结果已经停止了几个符合条件的条目。使用Sql Server 2008 V 10.非常感谢任何帮助

Answer 1

假设SQL Server 2005+，您可以使用：

;WITH CTE AS
(
    SELECT [ID],
           [Type],
           [Date],
           RN = ROW_NUMBER() OVER(PARTITION BY [ID] ORDER BY [Date] DESC)
    FROM YourTable
    WHERE [Type] = 'A'
)
SELECT A.[ID], 
       A.[Date] [Date A],
       B.[Date] [Date B]
FROM (SELECT *
      FROM CTE
      WHERE RN = 1) A
CROSS APPLY (SELECT TOP 1 [Date]
             FROM YourTable
             WHERE [Type] = 'B'
             AND [ID] = A.[ID]
             AND [Date] > A.[Date]
             ORDER BY [Date]) B

结果是：

╔════╦═════════════════════════════════╦═════════════════════════════════╗
║ ID ║             DATE A              ║             DATE B              ║
╠════╬═════════════════════════════════╬═════════════════════════════════╣
║  2 ║ February, 10 2013 00:00:00+0000 ║ February, 15 2013 00:00:00+0000 ║
║  3 ║ March, 15 2013 00:00:00+0000    ║ March, 20 2013 00:00:00+0000    ║
╚════╩═════════════════════════════════╩═════════════════════════════════╝

here is你可以试试。{/ p>

Answer 2

您可以使用：

SELECT ID, A_Date, B_Date
FROM (
    SELECT a.ID,a.Date 'A_Date', b.Date 'B_Date', ROW_NUMBER() OVER (PARTITION BY a.ID ORDER BY DATEDIFF(day,a.Date,b.Date))'RowRank'
    FROM (SELECT ID,Type, MAX(Date)'Date'
          FROM Table1
          WHERE Type = 'A'
          GROUP BY ID,Type
          )a
    JOIN Table1 b
      ON a.ID = b.ID
      AND a.Type <> b.Type
      AND a.Date < b.Date
  )sub
WHERE RowRank = 1

演示：SQL Fiddle

Sql Server返回最大和最大日期的最大日期和日期

2 个答案: