SELECT
I.ITEM_CODE AS CODE,
CASE 
 WHEN I.ITEM_NAME <> IH.ITEM_NAME THEN I.ITEM_NAME
 WHEN I.ITEM_NAME = IH.ITEM_NAME THEN NULL 
 END AS NAME
 
FROM
 ITEM AS I
  INNER JOIN ITEM_HISTORY AS IH
  ON I.ITEM_CODE = IH.ITEM_CODE
  
ORDER BY
 I.ITEM_CODE DESC;