select
 ifnull(a.ITEM_CODE, b.ITEM_CODE) AS CODE
    , ifnull(a.ITEM_NAME, b.ITEM_NAME) AS NAME
    ,
case
when b.ITEM_CODE is null
then 'ADDED'

when a.ITEM_CODE is null
then 'DELETED'

when a.USER_UPDATE_DATETIME <> b. USER_UPDATE_DATETIME
then 'UPDATED'

end 
 as COMP_RSLT


from ITEM as a
full outer join  ITEM_HISTORY as b
on a.ITEM_CODE = b.ITEM_CODE

where a.USER_UPDATE_DATETIME is not b.USER_UPDATE_DATETIME

order by CODE desc