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 as order_num, o.OrderTotal as OrderTotal
from 
    (
        select a.order_num, SUM(a.quantity * a.item_price) as OrderTotal
        from OrderItems a
        group by a.order_num
    ) o, Customers c, Orders b
where c.cust_id = b.cust_id and b.order_num = o.order_num
order by c.cust_name asc, o.order_num asc