go
create function antalhverdageiMinutter(@aar int ,@maaned int)
-- returnerer antal minutter i hverdage i den pågældende måned
returns int
as
begin
declare @res int
declare @firstdayofmonth date = datefromparts(@aar,@maaned,1)
declare @firstdayofnextmonth date = dateadd(mm,1,@firstdayofmonth)
declare @lastdateofmonth date = dateadd(dd,-1,@firstdayofnextmonth)
if day(@lastdateofmonth) = 28
	set @res = 20
else
	if day(@lastdateofmonth) = 29
		if datename(DW,@firstdayofmonth) in ('Saturday','Sunday')
			set @res = 20
		else
			set @res = 21
	else
		if day(@lastdateofmonth) = 30
			if datename(DW,@firstdayofmonth) = 'Saturday'
				set @res = 20
			else
				if datename(DW,@firstdayofmonth) in ('Friday','Sunday')
					set @res = 21
				else set @res = 22
		else
			if day(@lastdateofmonth) = 31
				if datename(DW,@firstdayofmonth) in ('Friday','Saturday')
					set @res = 21
				else
					if datename(DW,@firstdayofmonth) in ('Thursday','Sunday')
						set @res = 22
					else set @res = 23
return 444*@res
end