select
  main.ITEM_CODE as CODE
 , case when hist.ITEM_NAME is null then main.ITEM_NAME
        when hist.ITEM_NAME = main.ITEM_NAME then null
        else main.ITEM_NAME
   end as NAME
from
    ITEM as main
left join
    ITEM_HISTORY as hist using(ITEM_CODE)
order by
     ITEM_CODE desc