UFN_APPUSER_ISPROXYUSER

                CREATE function dbo.UFN_APPUSER_ISPROXYUSER (@ID uniqueidentifier)
                returns bit
                as begin
                    declare @ISPROXYUSER bit = 0;

                    select @ISPROXYUSER = ISPROXYUSER
                    from dbo.APPUSER
                    where ID = @ID;

                    return @ISPROXYUSER;
                end