with deleted as (
    select
        ITEM_CODE as CODE
        , ITEM_NAME as NAME
        , 'DELETED' as COMP_RSLT
    from
        ITEM_HISTORY ih
    where not exists(
            select 1 from ITEM i where ih.ITEM_CODE = i.ITEM_CODE
        )
), added as (
    select
        ITEM_CODE as CODE
        , ITEM_NAME as NAME
        , 'ADDED' as COMP_RSLT
    from
        ITEM i
    where not exists(
            select 1 from ITEM_HISTORY ih where i.ITEM_CODE = ih.ITEM_CODE
        )
), updated as (
    select
        i.ITEM_CODE as CODE
        , i.ITEM_NAME as NAME
        , 'UPDATED' as COMP_RSLT
    from
        ITEM i
        inner join
            ITEM_HISTORY ih
        on
            i.ITEM_CODE = ih.ITEM_CODE
            and i.USER_UPDATE_DATETIME != ih.USER_UPDATE_DATETIME
)

select
    CODE
    , NAME
    , COMP_RSLT
from
    (
        select * from deleted
        union all
        select * from added
        union all
        select * from updated
    )
order by
    CODE desc
;