题解 | #21年8月份练题总数#
返回每个顾客不同订单的总金额
http://www.nowcoder.com/practice/ce313253a81c4947b20e801cd4da7894
****用的join 也行 select o.cust_id, sum(item_price * quantity )as total_order from Orders o inner join OrderItems oi on oi.order_num = o.order_num group by o.cust_id order by total_order desc
