题解 | #牛客的课程订单分析(七)#

select ifnull(c.name,'GroupBuy') source,count(1)
from order_info o left join client c
on o.client_id = c.id
where user_id in (
	select user_id
	from order_info
	where date > '2025-10-15'
	and product_name in ('C++','Java','Python')
	and status = 'completed'
	group by user_id
	having count(user_id) > 1
) 
and o.date > '2025-10-15'
and o.product_name in ('C++','Java','Python')
and o.status = 'completed'
group by c.name
order by source