with added as (
  select ITEM.ITEM_CODE, ITEM.ITEM_NAME from ITEM left join ITEM_HISTORY on ITEM.ITEM_CODE = ITEM_HISTORY.ITEM_CODE
  where ITEM_HISTORY.ITEM_NAME IS NULL
),
updated AS (
  select ITEM.ITEM_CODE, ITEM.ITEM_NAME from ITEM join ITEM_HISTORY on ITEM.ITEM_CODE = ITEM_HISTORY.ITEM_CODE
  where ITEM.USER_UPDATE_DATETIME != ITEM_HISTORY.USER_UPDATE_DATETIME
),
deleted AS (
  select ITEM_HISTORY.ITEM_CODE, ITEM_HISTORY.ITEM_NAME from ITEM_HISTORY left join ITEM on ITEM.ITEM_CODE = ITEM_HISTORY.ITEM_CODE
  where ITEM.ITEM_NAME IS NULL
)

select ITEM_CODE as CODE, ITEM_NAME as NAME, COMP_RESULT from
(
select *, 'ADDED' as COMP_RESULT from added
union all
select *, 'UPDATED' as COMP_RESULT from updated
union all
select *, 'DELETED' as COMP_RESULT from deleted
)
order by CODE
;