Funzionerà per intervalli con chiamate ...
Declare @datetimestart datetime
Declare @interval int
Set @datetimestart = '2009-01-01 12:00:00'
Set @interval = 5 --in minutes
Select
[start_interval], [end_interval] , count([start_interval]) as [calls]
From
(
Select
DateAdd( Minute,Floor(DateDiff(Minute,@datetimestart,[date])/@interval)*@interval
,@datetimestart) ,
DateAdd( Minute,@interval + Floor(DateDiff(Minute,@datetimestart,[date])/@interval)*@interval
,@datetimestart)
From yourTable
) As W([start_interval],[end_interval])
group by [start_interval], [end_interval]
Funzionerà per tutti gli intervalli, indipendentemente dal numero di chiamate ..
Declare @datetimestart datetime, @datetimeend datetime, @datetimecurrent datetime
Declare @interval int
Set @datetimestart = '2009-01-01 12:00:00'
Set @interval = 10
Set @datetimeend = (Select max([date]) from yourtable)
SET @datetimecurrent = @datetimestart
declare @temp as table ([start_interval] datetime, [end_interval] datetime)
while @datetimecurrent < @datetimeend
BEGIN
insert into @temp select (@datetimecurrent), dateAdd( minute, @interval, @datetimecurrent)
set @datetimecurrent = dateAdd( minute, @interval, @datetimecurrent)
END
Select
*
From
(
Select
[start_interval],[end_interval], count(d.[start_time])
From @temp t left join yourtable d on d.[start_time] between t.[start_interval] and t.[end_interval]
) As W([start_interval],[end_interval], [calls])
