题解 | #分组计算练习题#
分组计算练习题
https://www.nowcoder.com/practice/009d8067d2df47fea429afe2e7b9de45
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
确实很疑惑，为啥count(distinct device_id)就不对了呢
#刷题#
