SQL Server ，按 24 小时时段拆分持续时间行

Question

我正在使用 sql server 2008 r2。我正在尝试将一行按 FromDate、Todate 之间的 24 小时时段范围划分。 例如，如果一个时间行给出如下，（FromDate，Todate之间的范围是4天，所以我想要4行）

ID   FromDate                 Todate     
---- ------------------------ -------------------------
1    2014-04-01 08:00:00.000  2014-04-04 12:00:00.000

我想看到这样的结果：

ID   FromDate                 Todate                   DateDiff(HH)
---- ------------------------ -----------------------------------
1    2014-04-01 08:00:00.000  2014-04-01 23:59:59.000  15
1    2014-04-02 00:00:00.000  2014-04-02 23:59:59.000  23
1    2014-04-03 00:00:00.000  2014-04-03 23:59:59.000  23
1    2014-04-04 00:00:00.000  2014-04-04 12:00:00.000  12

Answer 1

试试这个查询：

WITH TAB1 (ID,FROMDATE,TODATE1,TODATE) AS
(SELECT ID,
FROMDATE,
DATEADD(SECOND, 24*60*60 - 1, CAST(CAST(FROMDATE AS DATE) AS DATETIME)) TODATE1,
TODATE 
FROM TABLE1
UNION ALL
SELECT 
ID,
DATEADD(HOUR, 24, CAST(CAST(TODATE1 AS DATE) AS DATETIME)) FROMDATE,
DATEADD(SECOND, 2*24*60*60-1, CAST(CAST(TODATE1 AS DATE) AS DATETIME)) TODATE1,
TODATE
FROM TAB1 WHERE CAST(TODATE1 AS DATE) < CAST(TODATE AS DATE)
),
TAB2 AS
(SELECT ID,FROMDATE,
CASE WHEN TODATE1 > TODATE THEN TODATE ELSE TODATE1 END AS TODATE
FROM TAB1)
SELECT TAB2.*,
DATEPART(hh, TODATE) - DATEPART(hh, FROMDATE) [DateDiff(HH)] FROM TAB2;

SQL Fiddle

Answer 2

http://sqlfiddle.com/#!6/36452/2

这应该是你需要的。 查询的第一部分是递归 CTE。这可用于创建日期数据。

WITH CTEDays AS
(
    SELECT CONVERT(date, '20140301') datevalue
 UNION ALL
    SELECT DATEADD(day, 1, C.datevalue)
    FROM CTEDays C
    WHERE DATEADD(day, 1, C.datevalue) <= '20140501'
)
SELECT 
    R.FromDate [FromOriginal]
    , R.ToDate [ToOriginal]
    , CDays.datevalue [RawDate]
    , WantedFrom = 
        CASE WHEN CONVERT(date, R.FromDate) = CDays.datevalue THEN R.FromDate
             ELSE CDays.datevalue
        END
    , WantedTo = 
        CASE WHEN CONVERT(date, R.ToDate) = CDays.datevalue THEN R.ToDate
             ELSE DATEADD(minute, 24*60-1, CONVERT(datetime, CDays.datevalue))
        END
FROM 
    tblRange R
    OUTER APPLY
    (
        SELECT C.datevalue
        FROM CTEDays C
        WHERE C.datevalue BETWEEN CONVERT(date, R.FromDate) AND CONVERT(date, R.ToDate)
    ) CDays

但是，如果 CTE 太慢或不方便，我建议为此设置一个日历表。

（正如我建议的here）

Answer 3

这应该可以满足您的需求。如果您在 from/to 范围内使用较大的日期范围，请记住设置 maxrecursion。

http://sqlfiddle.com/#!6/68b32/233

declare @tblTemp TABLE (id int identity, fromDate datetime, toDate datetime)

insert @tblTemp(fromDate, toDate)
select '2014-01-01 12:00:00', '2014-01-02 12:00:00'
union select '2014-04-01 12:00:00', '2014-04-02 12:00:00'


;with cte(i, f, t, e) as (
    select id as i, fromDate as f, DATEADD(SS, -1, DATEADD(HH, 1, fromDate)) as t, toDate as e
    from @tblTemp
    union all
    select cte.i as i, DATEADD(SS, 1, cte.t), DATEADD(HH, 1, cte.t) as t, cte.e as e
    from cte
    where DATEADD(HH,1,cte.t) <= cte.e
)
select i, f, t 
from cte
order by i,f