在SQL Server上计算切换间隔的秒数

我有一张这样的桌子：

Value TimeStamp
1   2016-04-01 00:01:09.000
0   2016-04-01 00:01:09.000
0   2016-04-01 00:01:37.000
1   2016-04-01 00:01:37.000
1   2016-04-01 00:04:52.000
1   2016-04-01 00:09:58.000
1   2016-04-01 00:15:05.000
1   2016-04-01 00:20:11.000
1   2016-04-01 00:24:49.000
1   2016-04-01 00:29:55.000
1   2016-04-01 00:31:19.000
0   2016-04-01 00:31:19.000
0   2016-04-01 00:31:46.000
1   2016-04-01 00:31:46.000
1   2016-04-01 00:35:01.000
1   2016-04-01 00:40:07.000
1   2016-04-01 00:44:46.000
1   2016-04-01 00:49:52.000
1   2016-04-01 00:54:58.000
1   2016-04-01 01:00:04.000
1   2016-04-01 01:01:28.000
0   2016-04-01 01:01:28.000
0   2016-04-01 01:05:10.000
0   2016-04-01 01:09:49.000

我想计算每天打开1次开关的秒数，这是交易；当时间戳重复时，这意味着开关值从0变为1，反之亦然，我已经有很多类似的方法：

Q1 AS (SELECT ROW_NUMBER() OVER (ORDER BY TimeStamp) AS id,
Value, Timestamp
FROM Q2
GROUP BY idVBox, sensorType, sensorSubtype, timeStamp
HAVING COUNT(TimeStamp) > 1)

Then:

SELECT A.Value, DATEDIFF(SECOND,A.TimeStamp,B.TimeStamp)
FROM Q1 AS A
INNER JOIN Q1 AS B
ON B.ID = A.ID + 1
AND B.ID%2 = 0

---

然后分组并求和，但这里的问题是，我不知道从过去的一天起值是1还是0，开关可以快速改变它的状态，并且永远不会得到它的实际状态的实际值。还有其他想法吗？

如果使用SQL Server 2012，则可以充分利用LAG函数。 首先，在value=1的重复日期加入表。接下来，计算on和上一个on之间的差值。最后，总结一下

注意：延迟将在当天的第一天返回null

SELECT 
    Seconds=SUM(X.Seconds)
FROM
(
    SELECT  
        Seconds=DATEDIFF(SECOND,LAG(T1.TimeStamp) OVER (ORDER BY T1.TimeStamp),T1.TimeStamp)    
    FROM
        MyTable T1
        INNER JOIN MyTable T2 ON T2.TimeStamp=T1.TimeStamp AND T1.Value<>T2.Value
    WHERE
        T1.Value=1
)AS X

---

您要做的是，在开始计算前的一天开始时，在集合中添加一个虚拟传感器状态开关

增加的额外记录包括：

0, '2016-04-01 00:00:00'
1, '2016-04-01 00:00:00' -- This is conditional on the first record in your set having a value of 1

下面是总体查询 注意：为了确定哪个记录实际上是序列中的第一个记录，我使用了ID列

;WITH Q0 AS(
    -- Inserts a new record ( 0, '2016-04-01 00:00:00' ) to the beginning of the day
    SELECT TOP 1 0 AS Value, CONVERT( DATETIME, CONVERT( DATE, LogDate )) AS LogDate
    FROM #SwitchLog
    UNION ALL
    -- Inserts a new record ( 1, '2016-04-01 00:00:00' ) to the beginning of the day when the first record has Value = 1
    SELECT Value, CONVERT( DATETIME, CONVERT( DATE, LogDate )) AS LogDate
    FROM
        ( SELECT TOP 1 ID, Value, LogDate
        FROM #SwitchLog
        ORDER BY LogDate ASC, ID ASC ) AS DummyRecord --<-- NOTE: the use of a table ID column
    WHERE Value = 1
    UNION ALL
    SELECT Value, LogDate
    FROM #SwitchLog
)
,
Q1 AS (SELECT ROW_NUMBER() OVER (ORDER BY LogDate) AS id,
SUM( Value ) AS Value, LogDate
FROM Q0
GROUP BY LogDate
HAVING COUNT(LogDate) > 1)

SELECT A.Value, DATEDIFF(SECOND,A.LogDate,B.LogDate) AS Total
FROM Q1 AS A
INNER JOIN Q1 AS B
ON B.ID = A.ID + 1 AND B.ID%2 = 0

---

应使用相同的方法在时段/日+1 00:00:00结束时插入虚拟记录，以适应一天结束时传感器值为1的情况。

您是否在计算关闭和打开之间的秒数？如何打开它，然后再打开？我错过了一些东西。您必须录制多个开关。总共有多少个开关？是的，我想计算在ON和OFF之间的时间，在序列中间的只有开关值为1的行，只有一个开关，当时间戳重复的时候，当开关被切换的时候。我的意思是说现在计数秒和1SI都看到了。你必须在那里做另一个等级才能得到它。“我本来打算采用一种简洁的方法，但没有领会到这一点。@豪尔赫，让我们看看其他人是否可以提交一个更好的答案，如果没有其他问题，请将答案标记为已接受。”。

SELECT 
    Seconds=SUM(X.Seconds)
FROM
(
    SELECT  
        Seconds=DATEDIFF(SECOND,LAG(T1.TimeStamp) OVER (ORDER BY T1.TimeStamp),T1.TimeStamp)    
    FROM
        MyTable T1
        INNER JOIN MyTable T2 ON T2.TimeStamp=T1.TimeStamp AND T1.Value<>T2.Value
    WHERE
        T1.Value=1
)AS X