题解 | #牛客的课程订单分析(三)#

方法一：找出满足条件的user_id,再对表进一步筛选。

select * from order_info 
where user_id 
in 
(
    select user_id from order_info 
    where product_name in ('C++','Python','Java') 
    and status = 'completed'
    and date > '2025-10-15' 
    group by user_id having count(user_id) > 1
) 
and product_name in ('C++','Python','Java') 
and status = 'completed'
and date > '2025-10-15' 
order by id;

方法二：窗口函数, 计数而已

select t.id,t.user_id,t.product_name,t.status,t.client_id,t.date
from
(select *, count(*) over(partition by user_id) as num
from order_info
where product_name in ('C++','Java','Python')
and status='completed'
and date >'2025-10-15') as t
where t.num >= 2
order by t.id;