DELETE FROM ITEM WHERE ITEM_CODE IN
(select
    it.ITEM_CODE 
from
    ITEM as it 
    left outer join STOCK as st 
        on it.ITEM_CODE = st.ITEM_CODE 
where
    it.STOCK_MANAGEMENT_TYPE = '1'
group by it.ITEM_NAME
HAVING MAX(st.LAST_DELIVERY_DATE) <= DATE('2023-06-01', 'localtime', '-6 MONTH')  
    or st.LAST_DELIVERY_DATE ISNULL);