delete from item where stock_management_type = 1 and not exists(
    select item_code
    from stock
    where stock.item_code = item.item_code
)
or exists(
    select item_code
    from stock
    where stock.item_code = item.item_code
    group by item_code
    having MAX(IFNULL(LAST_DELIVERY_DATE, '2999-12-31')) <= DATE ('2023-06-01', '-6 months') 
    and SUM(ACTUAL_AMT) = 0
);