题解 | #牛客的课程订单分析(七)#

SELECT if(t.client_id = 0,"GroupBuy",name) source,count(1)
FROM(
    select client_id
    from order_info
    where 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) >=2
        order by user_id
    ) and date>"2025-10-15" and status = "completed" and product_name in ("C++","Java","Python")
)t LEFT JOIN client ON client.id = t.client_id
group by source
order by source