delete from ITEM
 where not exists(select 1 from STOCK b
                    where b.ITEM_CODE = ITEM.ITEM_CODE)
    or (STOCK_MANAGEMENT_TYPE = 1
    and exists(select 1 from STOCK b
                where b.ITEM_CODE = ITEM.ITEM_CODE
                  and b.ACTUAL_AMT = 0
               group by b.ITEM_CODE
                having max(b.LAST_DELIVERY_DATE) <= '2023-01-01')
              )