题解 | #牛客的课程订单分析(六)#

select o.id,o.is_group_buy,case when o.is_group_buy='NO' then c.name else  'None' end client_name
from order_info o left join client c on o.client_id=c.id 
where o.user_id in(select user_id   #___查找符合条件的user_id
from order_info
where status='completed' and date>'2025-10-15' and product_name in ('C++','Java','Python')
group by user_id
having count(*)>=2) and status='completed' and date>'2025-10-15' and product_name in ('C++','Java','Python')
order by o.id