delete from
    STOCK
where
    ITEM_CODE in (
        select
            ITEM_CODE
        from
            STOCK
        group by
            STOCK.ITEM_CODE
        having
            max(date(coalesce(LAST_DELIVERY_DATE, '2023-06-01'))) <= date('2023-06-01', '-6 month')
            and sum(ACTUAL_AMT) = 0
    );

delete from
    ITEM
where not exists(
        select
            ITEM_CODE
        from
            STOCK
        where
            ITEM.ITEM_CODE = STOCK.ITEM_CODE
    );