题解 | #SQL类别高难度试卷得分的截断平均值#
返回购买 prod_id 为 BR01 的产品的所有顾客的电子邮件（一）
http://www.nowcoder.com/practice/962b16554fbf4b99a87f4d68020c5bfb
select cust_email
from Customers AS c
left join Orders as o
on c.cust_id = o.cust_id
left join OrderItems as oi
on oi.order_num = o.order_num
where oi.prod_id = 'BR01'
