题解 | #返回顾客名称和相关订单号以及每个订单的总价#
返回顾客名称和相关订单号以及每个订单的总价
https://www.nowcoder.com/practice/4dda66e385c443d8a11570a70807d250
- 子查询的方法
- group by 在where之后，order by之前
- 子查询只能查一列
- 必须在子查询内使用where联结
select cust_name,o.order_num,( select sum(quantity*item_price) from OrderItems oi where oi.order_num=o.order_num group by order_num ) as OrderTotal from Customers c, Orders o where c.cust_id=o.cust_id order by cust_name,order_num
