题解 | #分组计算练习题#
分组计算练习题
https://www.nowcoder.com/practice/009d8067d2df47fea429afe2e7b9de45
--主要是对学校和性别进行分组 ,使用 group by 注意:多个分组用 英文 , 隔开,统计用 count(),平均计算用 avg() select gender,university, count(gender) as usr_num, avg(active_days_within_30) as avg_active_day, avg(question_cnt) as avg_question_cnt from user_profile group by university,gender