-- select dbo.fGetMablaghFactor(7493,28)
alter function fGetMablaghFactor(@Bar_ID int , @Dom_ID_Noe smallint) returns decimal(19,4) as    
begin    
declare @t decimal(19,4);   
set @t= isnull((
select 
	sum((d.mablagh*d.meghdar1*d.meghdar2*d.tedad) + 
	(case when d.Taf_ID_ArzeshAfzoodeh is not null then isnull(d.MablaghArzeshAfzoodeh,0) else 0 end) -
	(case when d.Taf_ID_Takhfif is not null then isnull(d.MablagheTakhfif,0) else 0 end))
from bargeh m
	inner join bargehDetail d on m.ID = d.Bar_ID and m.ID = @Bar_ID
),0);  

select @t = @t + isnull(MablaghEzafeh,0) from Bargeh where Taf_ID_Ezafeh is not null and ID = @Bar_ID
select @t = @t - isnull(MablaghTakhfif,0) from Bargeh where Taf_ID_Takhfif is not null and ID = @Bar_ID
 
return @t    
end