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