delete from ITEM
where ITEM.STOCK_MANAGEMENT_TYPE = 1
and (not exists(select *
				from STOCK s
				where s.ITEM_CODE = ITEM.ITEM_CODE)
	or exists(select *
				from (select s.ITEM_CODE,max(s.LAST_DELIVERY_DATE) LAST_DELIVERY_DATE ,sum(ACTUAL_AMT) ACTUAL_AMT
						from STOCK s
						group by s.ITEM_CODE
						having sum(ACTUAL_AMT)=0) s
				where s.ITEM_CODE = ITEM.ITEM_CODE
				and s.LAST_DELIVERY_DATE <= datetime('2023-06-01', '-6 months')))