题解 | #牛客的课程订单分析(七)#

select
    case WHEN is_group_buy = 'No' THEN name
         WHEN is_group_buy = 'Yes' THEN 'GroupBuy'
    end as 'source',
    count(*) as cnt
from (
    select
        id,
        is_group_buy,
        client_id,
        count(user_id) over (partition by user_id) as cnt
    from order_info
    where
        date > '2025-10-15' AND
        status = 'completed' AND
        product_name in ('C++','Java','Python')
) as oi
left join client c
on oi.client_id = c.id
where oi.cnt >= 2
group by source
order by source