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