SELECT
    coalesce(I.ITEM_CODE, IH.ITEM_CODE) AS CODE
    ,coalesce(I.ITEM_NAME, IH.ITEM_NAME) AS NAME
    ,CASE WHEN I.USER_UPDATE_DATETIME <> IH.USER_UPDATE_DATETIME
          THEN 'UPDATED' 
          WHEN IH.ITEM_CODE IS NULL
          THEN 'ADDED'
          WHEN  I.ITEM_CODE IS NULL
          THEN 'DELETED'
          END AS COMP_RSLT
FROM
    ITEM AS I
FULL OUTER JOIN
    ITEM_HISTORY AS IH
  ON
    I.ITEM_CODE = IH.ITEM_CODE
WHERE
    I.USER_UPDATE_DATETIME IS NOT IH.USER_UPDATE_DATETIME
ORDER BY
    CODE DESC;