题解 | #返回购买 prod_id 为 BR01 的产品#
返回购买 prod_id 为 BR01 的产品的所有顾客的电子邮件（一）
https://www.nowcoder.com/practice/962b16554fbf4b99a87f4d68020c5bfb
select
cust_email
from
Customers as a
where a.cust_id in(
select
cust_id
from
Orders as a
join OrderItems using(order_num)
where prod_id = 'BR01'
)
