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 LAST_DELIVERY_DATE is not null
        and LAST_DELIVERY_DATE <= date('2023-06-01', '-6 months')
        and ACTUAL_AMT = 0
        and ITEM.STOCK_MANAGEMENT_TYPE = 1
    )