题解 | 返回顾客名称和相关订单号以及每个订单的总价
select
c.cust_name,
o.order_num,
(oi.quantity * oi.item_price) OrderTotal
from
Customers c
inner join Orders o on c.cust_id = o.cust_id
inner join OrderItems oi on oi.order_num = o.order_num
order by
c.cust_name,
o.order_num