Pytanie dotyczące SQL Server

Działa to w interwałach z połączeniami ...

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]

To będzie działać we wszystkich interwałach, niezależnie od liczby połączeń ..

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])