题解 | #牛客的课程订单分析(七)#

with t1 as (select t1.id,is_group_buy,
case when is_group_buy='Yes' then 'GroupBuy'
when is_group_buy='No' then name end source
from order_info t1
left join client t2
on t1.client_id = t2.id
where date>'2025-10-15'
and status='completed'
and product_name in ('C++','Java','Python')
and user_id in (
select user_id from order_info
where date>'2025-10-15'
and status='completed'
and product_name in ('C++','Java','Python')
group by user_id
having count(*)>1)
order by id asc)

select source,count(1) cnt
from t1
group by source order by source