Question

考虑到开始和结束时间，我想知道在给定时间内有多少分钟被覆盖。

create function CalcMinsInHour(@start datetime, @end datetime, @hour int)
returns int
as
begin
    --Looking for best way to write this part
end

CalcMinsInHour('2012-01-18 8:15', '2012-01-18 10:30', 7)  should return 0
CalcMinsInHour('2012-01-18 8:15', '2012-01-18 10:30', 8)  should return 45
CalcMinsInHour('2012-01-18 8:15', '2012-01-18 10:30', 9)  should return 60
CalcMinsInHour('2012-01-18 8:15', '2012-01-18 10:30', 10) should return 30
CalcMinsInHour('2012-01-18 8:15', '2012-01-18 10:30', 11) should return 0

编辑：@Start和@End代表员工的时钟输入/输出时间。所以是的，当他们工作超过午夜时，他们可以跨越两天，但不会超过这个。

Answer 1

这应该可以解决问题：

ALTER FUNCTION dbo.CalcMinsInHour(@start DATETIME, @end DATETIME, @hour INTEGER)
RETURNS INTEGER 
AS
BEGIN
    DECLARE @StartOfHour DATETIME
    DECLARE @EndOfHour DATETIME
    SELECT @StartOfHour = DATEADD(hh, @hour, CAST(CAST(@start AS DATE) AS DATETIME))
    IF NOT (@StartOfHour BETWEEN @start and @end)
        SET @StartOfHour = DATEADD(hh, @hour, CAST(CAST(@end AS DATE) AS DATETIME))

    SELECT @EndOfHour = DATEADD(hh, 1, @StartOfHour)

RETURN
(
SELECT 
    CASE WHEN @EndOfHour < @start OR @StartOfHour > @end THEN 0 ELSE
        DATEDIFF(mi,
            CASE WHEN @StartOfHour <= @start THEN @start ELSE @StartOfHour END,
            CASE WHEN @EndOfHour > @end THEN @end ELSE @EndOfHour END)  
    END
)
END

Answer 2

你能使用DateDiff吗？

select DATEDIFF(Minute, '2011-11-10 00:00:59.900', '2011-11-10 00:01:00.100')

Answer 3

这是计算总分钟数的函数（也适用于多天）：

create function CalcMinsInHour(@start datetime, @end datetime, @hour int)
    returns int
as
begin

    declare @selecterHourIntervals table (HourStart datetime, HourEnd datetime)
    declare @currentDate datetime

    /* start in the @start date, but the hour we want to count */
    set @currentDate = dateadd(hour, @hour, convert(datetime, convert(date, @start)))

    /* for every day between @start-@end add out hour interval */
    while @currentDate <= @end
    begin 
        insert into @selecterHourIntervals values (
                        @currentDate, 
                        dateadd(hour, 1, @currentDate))

        set @currentDate = dateadd(day, 1, @currentDate)
    end

    declare @totalMinutes int

    /* for every hour interval in the table, select number of minutes 
       trimmed by the @start - @end interval and sum */
    select @totalMinutes = sum(DailyMinutes)
    from
        (select
            datediff(minute,
            case when HourStart > @start then HourStart else @start end,
            case when HourEnd < @end then HourEnd else @end end) as DailyMinutes
        from @selecterHourIntervals) TrimmedIntervals
    where DailyMinutes > 0

    return isnull(@totalMinutes, 0)

end

计算给定小时内使用的分钟数

3 个答案: