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,
    a.order_num,
    OrderTotal
from (
    select 
        order_num,
        quantity*item_price OrderTotal
    from 
        OrderItems
) a ,
(
    select 
        order_num,
        cust_name
    from 
        Customers inner join Orders
    on 
        Customers.cust_id = Orders.cust_id
) b 
WHERE
    a.order_num = b.order_num
order by 
    cust_name,
    a.order_num;










select 
    order_num,
    cust_name
from 
    Customers inner join Orders
on 
    Customers.cust_id = Orders.cust_id;


select 
    order_num,
    quantity*item_price OrderTotal
from 
    OrderItems;