-- 写経
SELECT
    COALESCE(IT_M.ITEM_CODE, IT_H.ITEM_CODE) AS CODE
,   COALESCE(IT_M.ITEM_NAME, IT_H.ITEM_NAME) AS NAME
,   CASE
        WHEN IT_H.USER_UPDATE_DATETIME IS NULL
            THEN "ADDED"
        WHEN IT_M.USER_UPDATE_DATETIME IS NULL
            THEN "DELETED"
        WHEN
            IT_M.USER_UPDATE_DATETIME <> IT_H.USER_UPDATE_DATETIME
            THEN "UPDATED"
    END AS COMP_RSLT
FROM
    ITEM AS IT_M
FULL OUTER JOIN
    ITEM_HISTORY AS IT_H
ON
    IT_M.ITEM_CODE = IT_H.ITEM_CODE
WHERE
    IT_M.USER_UPDATE_DATETIME IS NOT IT_H.USER_UPDATE_DATETIME
ORDER BY
    CODE DESC;