题解 | #分组过滤练习题#
分组过滤练习题
http://www.nowcoder.com/practice/ddbcedcd9600403296038ee44a172f2d
select u.university, u.avg_question_cnt, u.avg_answer_cnt from (select university, round(avg(question_cnt),3) as avg_question_cnt, round(avg(answer_cnt),3) as avg_answer_cnt from user_profile group by university) as u where u.avg_question_cnt<5 or avg_answer_cnt<20;
子查询方式查询，试了一下比较慢