题解 | #返回顾客名称和相关订单号以及每个订单的总价#

with t as
(
    select order_num,sum(quantity*item_price) 'OrderTotal'
    from OrderItems 
    group by order_num 
)
select c.cust_name,t.order_num,t.OrderTotal
from Orders o join Customers c using(cust_id)
join t using(order_num)
order by c.cust_name,t.order_num asc;