UFN_GROUPMEMBER_ISCURRENTMEMBER

            CREATE function dbo.UFN_GROUPMEMBER_ISCURRENTMEMBER(@GROUPMEMBERID uniqueidentifier)
            returns bit
            as
            begin
                declare @result bit
                declare @CURRENTDATEEARLIESTTIME date;
                set @CURRENTDATEEARLIESTTIME = getdate();

                select @result = case when count(GROUPMEMBER.ID) = 1 then 1 else 0 end from dbo.GROUPMEMBER
                left join dbo.GROUPMEMBERDATERANGE GMDR on GMDR.GROUPMEMBERID = GROUPMEMBER.ID
                where GROUPMEMBER.ID = @GROUPMEMBERID and
                ((GMDR.DATEFROM is null and (GMDR.DATETO is null or GMDR.DATETO > @CURRENTDATEEARLIESTTIME))
                or (GMDR.DATETO is null and (GMDR.DATEFROM is null or GMDR.DATEFROM <= @CURRENTDATEEARLIESTTIME)) 
                or (GMDR.DATEFROM <= @CURRENTDATEEARLIESTTIME and GMDR.DATETO > @CURRENTDATEEARLIESTTIME))

                return @result;
            end