我有这个表（MachineLog）
ID BeltBit timeStamp
------------------------------------------
4561 0 2014 03 10 07:56:03.953
4562 0 2014 03 10 07:56:04.370
4563 0 2014 03 10 07:56:04.960
4564 0 2014 03 10 13:25:33.833
4565 1 2014 03 10 13:27:12.113
4566 1 2014 03 10 13:27:51.203
4567 0 2014 03 10 13:54:08.727
4568 1 2014 03 10 13:56:16.523
4569 1 2014 03 10 13:56:39.260
4570 1 2014 03 10 13:56:39.580
我想构建一个查询来获得此结果：
StartID EndID BeltBit StartStamp EndStamp Interval (in sec)
-----------------------------------------------------------------------------------------------
4561 4564 0 2014 03 10 07:56:03.953 2014 03 10 13:27:12.113 19869
4565 4566 1 2014 03 10 13:27:12.113 2014 03 10 13:54:08.727 1616
4567 4567 0 2014 03 10 13:54:08.727 2014 03 10 13:56:16.523 128
4568 4570 1 2014 03 10 13:56:16.523 2014 03 10 13:56:39.580 23
我想通过beltbit分组（所有连续的belbit状态相同）并计算它们的间隔...
请注意：此表包含数百万条记录，因此多个连接速度极慢。
我使用sql-2012 LAG和LEAD函数找到了这样的查询如果有任何增强功能请告诉我
; WITH Level1 AS ( SELECT ID , BeltBit , timeStamp AS EventDateTime , LAG(BeltBit, 1, null) OVER ( PARTITION BY 1 ORDER BY timestamp ) AS LastEvent , LEAD(BeltBit, 1, null) OVER ( PARTITION BY 1 ORDER BY timestamp) AS NextEvent FROM MachineLog ),等级2
AS ( SELECT ID ,
BeltBit ,
EventDateTime ,
LastEvent ,
NextEvent
FROM Level1
WHERE NOT ( BeltBit = 0
AND LastEvent = 0
)
AND NOT ( BeltBit = 1
AND NextEvent = 1
)
),
Level3
AS ( SELECT ID ,
BeltBit ,
EventDateTime ,
DATEDIFF(second, EventDateTime,
LEAD(EventDateTime)
OVER ( PARTITION BY 1
ORDER BY EventDateTime )) AS Seconds
FROM Level2
)
select * from Level3