题解 | #牛客的课程订单分析(七)#
牛客的课程订单分析(七)
https://www.nowcoder.com/practice/d6f4a37f966145da8900ba9edcc4c068
select a.source,count(a.source) cnt from (select ifnull(c.name,'GroupBuy') source,user_id from order_info o left join client c on o.client_id=c.id where datediff(date,'2025-10-15')>0 and product_name in ('C++','Java','Python') and status='completed' and o.user_id in ( select user_id from order_info where datediff(date,'2025-10-15')>0 and product_name in ('C++','Java','Python') and status='completed' group by user_id having count(*)>1 )) a group by a.source order by a.source
- 利用表连接得到渠道和订单的表
- 利用筛选条件得到符合要求的订单
- 还包括子查询得到下单两次的用户
- 然后使用groupby的到最终结果