题解 | #牛客的课程订单分析(三)#

select
    oi.*
from
order_info oi
inner join 
  (
        select
            user_id,
            sum(
                case
                    status
                    when 'completed' then 1
                    else 0
                end
            ) completedNum
        from
            order_info
        where
            date > '2025-10-15'
            and product_name in ('C++', 'Python', 'Java')
        group by
            user_id
        having completedNum>=2
    ) t1
    using(user_id)
 where
    date > '2025-10-15'
    and product_name in ('C++', 'Python', 'Java')
    and status='completed'
order by
    id