select ITEM.ITEM_CODE as CODE
,case
    when ITEM.ITEM_NAME <> ITEM_HISTORY.ITEM_NAME
     then ITEM.ITEM_NAME
    when ITEM.ITEM_NAME = ITEM_HISTORY.ITEM_NAME
     then NULL     
    else ITEM.ITEM_NAME
    end as NAME
from ITEM
left join ITEM_HISTORY
on ITEM.ITEM_CODE = ITEM_HISTORY.ITEM_CODE
order by ITEM.ITEM_CODE desc