UFN_SITEID_MAPFROM_REVENUELETTERID

             CREATE function dbo.UFN_SITEID_MAPFROM_REVENUELETTERID  
             (  
            @REVENUELETTERID uniqueidentifier  
             )   
                returns table
                as  
            return
            (
                select REVENUESITE.SITEID
                from dbo.REVENUELETTER
        cross apply dbo.UFN_SITEID_MAPFROM_REVENUEID_2(REVENUELETTER.REVENUEID) REVENUESITE
                where REVENUELETTER.ID = @REVENUELETTERID
            );