题解 | #分组过滤练习题#
分组过滤练习题
https://www.nowcoder.com/practice/ddbcedcd9600403296038ee44a172f2d
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 having avg(question_cnt) < 5 or avg(answer_cnt) < 20;
where不能对聚合函数进行判断，所以用having
