此过程的光标替代方法？

我有了这种格式记录的表：此过程的光标替代方法？

SPECIAL_ID | OTHER_ID | NAME | TIMESTAMP

我需要创建基于关闭的这个新表，但只拿到相距至少25分钟从以前的一个记录。间隔不一致。所以，如果我从记录1开始，我需要从记录1的时间戳中获取至少25分钟的下一个记录。这将是新表中的记录2。然后下一个记录是上一个提取后的25分钟。所以，这里是信息的一个例子：

AAA | 1 | WHATEVER2 | 2016-11-20 00:00:00 
BCD | 2 | WHATEVER00 | 2016-11-20 00:02:00 
AAA | 3 | WHATEVER01 | 2016-11-20 00:09:00 
AAA | 4 | WHATEVER55 | 2016-11-20 00:20:00 
XYZ | 5 | WHATEVER | 2016-11-20 00:24:00 
AAA | 6 | WHATEVER11 | 2016-11-20 00:45:00 
QRS | 7 | WHATEVER | 2016-11-20 00:46:00 
QRS | 8 | WHATEVER12 | 2016-11-20 00:59:00 
AAA | 9 | WHATEVER12 | 2016-11-20 01:02:00 
AAA |10 | WHATEVER12 | 2016-11-20 01:17:00

什么我试图做的事：

AAA | 1 | WHATEVER2 | 2016-11-20 00:00:00 
AAA | 6 | WHATEVER11 | 2016-11-20 00:45:00 
AAA |10 | WHATEVER12 | 2016-11-20 01:17:00

我设法使用游标并测试了一小部分的记录。它的工作....但我有百万记录，需要用这种方式进行分析。看起来，光标只是要求麻烦。

有没有更好的方法来做到这一点？

我被SQL Server 2008卡住了，所以lead()和lag()是不可能的。

任何帮助非常感谢。

来源

2016-11-20 user3150002

这可能是用于SQL Server 2008的可能的（计算上昂贵的）溶液：

在第一步骤中，第一记录被确定。在第二步中，查询为每个现有记录确定最近的25分钟记录。随后（步骤3），将数据记录缩小到具有最低OTHER_ID的数据记录。当然，这只适用于OTHER_ID为唯一且与时间同步增加的字段。对于数百万条记录，应该对查询中使用的字段进行索引并限制搜索。

-- test script 

SET dateformat ymd 

;WITH testdata AS (
    SELECT 'AAA'  AS SPECIAL_ID, 
     1   AS OTHER_ID, 
     'WHATEVER2' AS NAME , 
     CONVERT(DATETIME, '2016-11-20 00:00:00') AS [TIMESTAMP] 
    UNION SELECT 'BCD' , 2 , 'WHATEVER00' , CONVERT(DATETIME, '2016-11-20 00:02:00') 
    UNION SELECT 'AAA' , 3 , 'WHATEVER01' , CONVERT(DATETIME, '2016-11-20 00:02:01') 
    UNION SELECT 'AAA' , 4 , 'WHATEVER55' , CONVERT(DATETIME, '2016-11-20 00:20:00') 
    UNION SELECT 'XYZ' , 5 , 'WHATEVER' , CONVERT(DATETIME, '2016-11-20 00:24:00') 
    UNION SELECT 'AAA' , 6 , 'WHATEVER11' , CONVERT(DATETIME, '2016-11-20 00:45:00') 
    UNION SELECT 'QRS' , 7 , 'WHATEVER' , CONVERT(DATETIME, '2016-11-20 00:46:00') 
    UNION SELECT 'QRS' , 8 , 'WHATEVER12' , CONVERT(DATETIME, '2016-11-20 00:59:00') 
    UNION SELECT 'AAA' , 9 , 'WHATEVER12' , CONVERT(DATETIME, '2016-11-20 01:02:00') 
    UNION SELECT 'AAA' ,10 , 'WHATEVER12' , CONVERT(DATETIME, '2016-11-20 01:17:00') 
    UNION SELECT 'QRS' ,11 , 'WHATEVER13' , CONVERT(DATETIME, '2016-11-20 01:30:00') 
), firstRecord AS (
    SELECT SPECIAL_ID, MIN(OTHER_ID) AS OTHER_ID 
    FROM testdata 
    GROUP BY SPECIAL_ID 
), nextRecord1 AS (
    SELECT I1.SPECIAL_ID, I1.OTHER_ID AS OTHER_ID, MIN(I2.OTHER_ID) AS next_OTHER_ID 
    FROM testdata I1 
     INNER JOIN testdata I2 
       ON I1.SPECIAL_ID = I2.SPECIAL_ID 
       AND I1.OTHER_ID < I2.OTHER_ID 
       AND I2.[TIMESTAMP] >= DATEADD(minute, 25, I1.[TIMESTAMP]) 
    GROUP BY I1.SPECIAL_ID, I1.OTHER_ID 
), nextRecord2 AS (
    SELECT SPECIAL_ID, MIN(OTHER_ID) AS OTHER_ID, next_OTHER_ID 
    FROM nextRecord1 
    GROUP BY SPECIAL_ID, next_OTHER_ID 
) 
SELECT T2.* 
    FROM firstRecord T1 
     INNER JOIN testdata T2 
       ON T1.OTHER_ID = T2.OTHER_ID 
UNION 
SELECT T2.* 
    FROM nextRecord2 T1 
     INNER JOIN testdata T2 
       ON T1.next_OTHER_ID = T2.OTHER_ID

来源

2016-11-20 22:32:57 fbcomps

此过程的光标替代方法？

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