with a as (
select
    ITEM_CODE 
    ,sum(ACTUAL_AMT) as amt_sum
    ,max(ifnul(LAST_DELIVERY_DATE,'2999-12-31')) as max_date
from STOCK
group by ITEM_CODE
)
delete
from ITEM
where 
(
    not exists 
        (select ITEM_CODE 
        from STOCK
        where STOCK.ITEM_CODE = ITEM.ITEM_CODE)
    or exists 
        (select ITEM_CODE from a
        where a.ITEM_CODE = ITEM.ITEM_CODE
        and max_date <= date('2023-06-01','-6 month')
        and amt_sum = 0)
)
and STOCK_MANAGEMENT_TYPE = 1