题解 | #返回顾客名称和相关订单号以及每个订单的总价#

SELECT
    p1.cust_name,
    p2.order_num,
    sum(quantity * item_price) as OrderTotal
FROM
    Customers as p1
    inner join Orders as p2 on p1.cust_id = p2.cust_id
    inner join OrderItems as p3 on p3.order_num = p2.order_num
GROUP BY
    p1.cust_name,p2.order_num
ORDER BY
    p1.cust_name,
    p2.order_num;