select A.ITEM_CODE AS CODE,
case WHEN b.ITEM_NAME is null then a.ITEM_NAME
WHEN a.ITEM_NAME = b.ITEM_NAME then NULL
else a.ITEM_NAME
end AS NAME
from ITEM A
left outer join ITEM_HISTORY B
on A.ITEM_CODE = B.ITEM_CODE
order by a.ITEM_CODE desc