如何从存储过程中返回多行？(Oracle PL/SQL)

  open mycursor for select * from table1;
  open mycursor2 for select * from table2;

    LOOP
      FETCH NEXT FROM mycursor1 INTO ...
      FETCH NEXT FROM mycursor2 INTO ...
      EXIT WHEN ...
      ...
    END LOOP;

  OPEN mycursor for select * from orders; -- 假设orders表包括订单ID、购买量、订单总额、订单状态等列。
  OPEN mycursor2 for select * from customers; -- 假设customers表包括用户ID、名字、年龄、地址等列。
  LOOP
    FETCH NEXT FROM mycursor INTO po_id, order_quantity, order_total FROM orderheader;
    FETCH NEXT FROM mycursor2 INTO cu_id, cu_name FROM customer;
    
    -- 在order_headers表中，如果total字段大于特定金额（例如1000元），则创建一个新行的order_total为当前total加上1000，并更新订单金额等于最后订单金额
    IF order_total > 1000 THEN
      UPDATE orderheader
         SET order_total = order_total + 1000,
             order_amount_paid = order_amount_paid + total - 1000
      WHERE order_id = po_id;
    ELSE
      ...
    END IF;
     
    -- 向order_payments表添加一行，该行包括id=order_id、payment_type=credit_card、amount=order_total等字段
    INSERT INTO order_payments (order_id, payment_type, amount) VALUES (po_id, 'credit_card', order_total);

    -- 检查订单状态是否为已付款，并将已处理字段设置为true的新行
    IF order_total >= order_amount_paid THEN
      UPDATE orderheader
         SET order_status = 'processed',
             order_processed_date = dbdt
      WHERE order_id = po_id;
    ...
  END LOOP;