题解 | #21年8月份练题总数#
分组计算练习题
http://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;