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我正在使用以下查询来查找列的空值，并使用以下查询获取空值的开始时间和结束时间约 30,000 行

    SELECT
    yt1.[timestamp] AS StartTime,
    MIN(yt2.[timestamp]) AS EndTime,
    DATEDIFF(MINUTE, yt1.[timestamp], MIN(yt2.[timestamp])) AS DifferenceInMinutes
    FROM
    Sheet1$ yt1
    LEFT JOIN Sheet1$ yt2 ON yt1.[timestamp] < yt2.[timestamp]
    WHERE
    yt1.TWSPD IS NULL
    GROUP BY yt1.[timestamp]

输出是

Start time                     Endtime                DifferenceInMinutes
2012-05-18 20:47:03.000    2012-05-18 20:57:04.000      10
2012-05-18 20:57:04.000    2012-05-18 21:07:04.000      10
2012-05-21 18:25:26.000    2012-05-21 18:35:26.000      10
2012-06-07 17:36:28.000    2012-06-07 17:46:28.000      10
2012-06-07 17:46:28.000    2012-06-07 17:56:28.000      10
2012-06-07 17:56:28.000    2012-06-07 18:06:28.000      10

例如，现在我需要输出为（删除了一些行以更好地显示）

Start time                     Endtime                DifferenceInMinutes
2012-05-18 20:47:03.000    2012-05-18 21:07:04.000      20
2012-05-21 18:25:26.000    2012-05-21 18:35:26.000      10
2012-06-07 17:36:28.000    2012-06-07 18:06:28.000      30

时间戳为每 10 分钟一次，如果要添加连续 10 分钟时间间隔的空值，则开始时间和结束时间应显示为从连续时间戳的第一个空值到最后一个空值。希望问题很清楚。如果我不清楚，请告诉我。请帮忙

4

2 回答 2

0 
 SELECT
    yt1.[timestamp] AS StartTime,
    MIN(yt2.[timestamp]) AS EndTime,
    DATEDIFF(MINUTE, yt1.[timestamp], MIN(yt2.[timestamp])) AS DifferenceInMinutes
    into #tmp1
    FROM
    Sheet1$ yt1
    LEFT JOIN Sheet1$ yt2 ON yt1.[timestamp] < yt2.[timestamp]
    WHERE
    yt1.TWSPD IS NULL
    GROUP BY yt1.[timestamp]


Select t1.* 
into #tmp2
from #tmp1 t1
left join #tmp1 t2 on t1.Starttime=t2.Endtime
where t2.Endtime is null

Declare @rcn int
Select @rcn=1
While @rcn>0
    begin
       Update #tmp2 set #tmp2.Endtime=t.endTime,#tmp2.DifferenceInMinutes=#tmp2.DifferenceInMinutes+t.DifferenceInMinutes
       from #tmp1 t
       where t.Starttime=#tmp2.Endtime
       select @rcn=@@Rowcount
    end


select * from #tmp2

Drop Table #tmp1
Drop Table #tmp2
于 2012-12-12T08:08:23.333 回答
0

如果您想查询原始表以具有分组输出 - 您可以这样做：

;with
CTE_start
as
(
    select T.timestamp, row_number() over(order by T.timestamp) as RowNum
    from temp1 as T
    where
        not exists 
        (
            select * 
            from temp1 as TT
            where TT.timestamp < T.timestamp and TT.timestamp >= dateadd(mi, -11, T.timestamp)
        )  
),
CTE_end
as
(
    select T.timestamp, row_number() over(order by T.timestamp) as RowNum
    from temp1 as T
    where
        not exists 
        (
            select * 
            from temp1 as TT
            where TT.timestamp > T.timestamp and TT.timestamp <= dateadd(mi, 11, T.timestamp)
        )  
)
select
    s.timestamp as [Start time],
    e.timestamp as [End time],
    datediff(mi, s.timestamp, e.timestamp) as [DifferenceInMinutes]
from CTE_start as s
    inner join CTE_end as e on e.RowNum = s.RowNum

SQL 提琴示例

另一个不错的，但是您必须将数据复制到临时（变量）表中

declare @tmp table (timestamp datetime, RowNum int primary key)

insert into @tmp
select T.timestamp, row_number() over(order by T.timestamp) as RowNum
from temp1 as T

;with CTE
as
(
    select T.timestamp, T.RowNum, 1 as GroupNum
    from @tmp as T
    where RowNum = 1
    union all
    select
        T.timestamp, T.RowNum,
        C.GroupNum + case when datediff(mi, C.timestamp, T.timestamp) >= 11 then 1 else 0 end
    from @tmp as T
        inner join CTE as C on C.RowNum + 1 = T.RowNum
)
select
    min(C.timestamp) as [Start time],
    max(C.timestamp) as [End time],
    datediff(mi, min(C.timestamp), max(C.timestamp)) as [DifferenceInMinutes]
from CTE as C
group by C.GroupNum

SQL 提琴示例

于 2012-12-12T08:09:52.257 回答