题解 | #分组计算练习题#
分组计算练习题
http://www.nowcoder.com/practice/009d8067d2df47fea429afe2e7b9de45
语句比较长
select gender,university, COUNT(device_id) as user_num,avg(active_days_within_30) as avg_active_day,
avg(question_cnt) as avg_question_cnt from user_profile group by gender,university;