UFN_SITEID_MAPFROM_SEGMENTATIONID

create function [BBDW].[UFN_SITEID_MAPFROM_SEGMENTATIONID]
  (  
    @SEGMENTATIONID uniqueidentifier  
  )   
  returns uniqueidentifier
    as  

    begin
      declare @ID uniqueidentifier;
      select @ID = case when s.[SITESYSTEMID] <> '00000000-0000-0000-0000-000000000000' then s.[SITESYSTEMID] else null end 
      from BBDW.[DIM_MARKETINGSEGMENT] ms
      inner join BBDW.[DIM_SITE] s on ms.[SEGMENTATIONSITEDIMID] = s.[SITEDIMID]
      where ms.[SEGMENTATIONSYSTEMID] = @SEGMENTATIONID
      return @ID
    end