How To Set Time Interval using SQL server

Question 1

declare @Start time
declare @end time
declare @request int

set @Start = '08:00:00'
set @end = '16:00:00'
set @request = 1

;with Dates as (
    select @request as reqId,@Start as reqDate
    union all
    select reqId+1,DATEADD(MINUTE,10,reqDate) from Dates
    where reqDate < @end
)
select reqId,convert(varchar(8),reqDate,100)+'-'+convert(varchar(8),DATEADD(MINUTE,10,reqDate),100) "Time Interval" from Dates

Use this for ur reports

Question 2

Take a look at DateDiff

SELECT DATEDIFF(second, '2000-01-01 08:00:00' , '2000-01-01 16:00:00');

Return the difference/interval in seconds. Divide by 60 to get minutes, and divide by 60 again to get hours.

Since you are only using the time component, you can set the datepart to whatever you like.

EDIT:

Since I misread the question, maybe you want something like this:

DateTime startAt = new DateTime(2000, 01, 01, 8, 0, 0);
DateTime endAt = new DateTime(2000, 01, 01, 16, 0, 0);

for (DateTime date = startAt; date < endAt; date = date.AddMinutes(10))
{
    // create something with this interval
    Console.WriteLine(string.Format("Interval start: {0}, Interval End: {1}", date.ToString("HH:mm"), date.AddMinutes(10).ToString("HH:mm")));
}

Just use the start date and end date and loop through it with 10min intervals.

Question 3

Here is a solution using CTE

DECLARE @StartDate DATETIME, @EndTime DATETIME

SELECT @StartDate = '8:00 PM'
SELECT @EndTime = '9:00 PM'


;WITH time_cte(StartTime, EndTime) AS
(
   SELECT @StartDate StartTime, DATEADD(mi, 10, @StartDate) EndTime

   UNION ALL

   SELECT EndTime, DATEADD(mi, 10, EndTime)  FROM time_cte
   WHERE EndTime < @EndTime

)  
SELECT * FROM time_cte

Check its working at SQL Fiddle