题解 | #牛客的课程订单分析(七)#
牛客的课程订单分析(七)
http://www.nowcoder.com/practice/d6f4a37f966145da8900ba9edcc4c068
SELECT
IFNULL(t1.name, "GroupBuy") AS source,
COUNT(*) AS cnt
FROM
(
SELECT *,
COUNT(*) OVER(PARTITION by user_id) AS num
FROM order_info
WHERE
date > "2025-10-15"
AND status = "completed"
AND product_name IN ("C++", "Python", "Java")
) AS t
LEFT JOIN client AS t1
ON t.client_id = t1.id
WHERE t.num > 1
GROUP BY source
ORDER BY source
