题解 | 牛客的课程订单分析(四)
牛客的课程订单分析(四)
https://www.nowcoder.com/practice/c93d2079282f4943a3771ca6fd081c23
select user_id,min(date) as first_buy_date, cnt
from (
select user_id,date,
count(*) over(partition by user_id) cnt
from order_info
where status='completed'
and date > '2025-10-15'
and product_name in ('C++','Java','Python')
)a
where cnt>1
group by user_id
order by user_id
