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(id) er_num, ROUND(avg(active_days_within_30),1) avg_active_day, ROUND(avg(question_cnt),1) avg_question_cnt FROM user_profile GROUP BY gender,university
