delete from
    ITEM
where
    not exists(
        select
            ITEM_CODE
        from
            STOCK
        where
            ITEM.ITEM_CODE = STOCK.ITEM_CODE
    )
    or 
    exists(
        select
            ITEM_CODE
        from
            STOCK
        where
            ITEM.ITEM_CODE = STOCK.ITEM_CODE
        and ITEM.STOCK_MANAGEMENT_TYPE = 1
        group by STOCK.ITEM_CODE
        having max(LAST_DELIVERY_DATE) is not null
        and max(case when LAST_DELIVERY_DATE is not null then LAST_DELIVERY_DATE else '2023-06-01' end) <= date('2023-06-01',  '-6 month') 
        and sum(ACTUAL_AMT) = 0
    )