SELECT
    I.ITEM_CODE AS CODE,
    CASE
        WHEN IH.ITEM_NAME IS NULL THEN I.ITEM_NAME
        WHEN I.ITEM_NAME <> IH.ITEM_NAME THEN I.ITEM_NAME
        ELSE NULL
    END AS NAME
FROM
    ITEM I
LEFT JOIN
    ITEM_HISTORY IH
ON
    I.ITEM_CODE = IH.ITEM_CODE
ORDER BY
    I.ITEM_CODE DESC;