题解 | #返回顾客名称和相关订单号以及每个订单的总价#

select cust_name,Orders.order_num,sum(quantity*item_price) OrderTotal
from Customers,Orders,OrderItems
where Customers.cust_id = Orders.cust_id and Orders.order_num = OrderItems.order_num
group by cust_name,Orders.order_num
order by cust_name,Orders.order_num