Count work days between two dates

Question

How can I calculate the number of work days between two dates in SQL Server?

Monday to Friday and it must be T-SQL.

Answer 1

DECLARE @StartDate datetime,@EndDate datetime

select @StartDate='3/2/2010', @EndDate='3/7/2010'

DECLARE @TotalDays INT,@WorkDays INT

DECLARE @ReducedDayswithEndDate INT

DECLARE @WeekPart INT

DECLARE @DatePart INT

SET @TotalDays= DATEDIFF(day, @StartDate, @EndDate) +1

SELECT @ReducedDayswithEndDate = CASE DATENAME(weekday, @EndDate)
    WHEN 'Saturday' THEN 1
    WHEN 'Sunday' THEN 2
    ELSE 0 END

SET @TotalDays=@TotalDays-@ReducedDayswithEndDate

SET @WeekPart=@TotalDays/7;

SET @DatePart=@TotalDays%7;

SET @WorkDays=(@WeekPart*5)+@DatePart

SELECT @WorkDays