题解 | #分组计算练习题#
分组计算练习题
http://www.nowcoder.com/practice/009d8067d2df47fea429afe2e7b9de45
SELECT gender, university, COUNT(device_id) as user_num, round(avg(active_days_within_30),1) AS avg_active_day, round(avg(question_cnt),1) AS avg_question_cnt FROM user_profile group by gender ,university
