SELECT 
T1.ITEM_CODE AS CODE,
CASE 
WHEN T2.ITEM_NAME IS NULL THEN T1.ITEM_NAME
WHEN T1.ITEM_NAME <> T2.ITEM_NAME THEN T1.ITEM_NAME 
ELSE NULL END AS NAME
FROM
ITEM T1
LEFT OUTER JOIN
ITEM_HISTORY T2
ON
T2.ITEM_CODE = T1.ITEM_CODE
ORDER BY
T1.ITEM_CODE DESC