运营想查看不同大学情况，就用大学分组 group by university
查看用户平均发帖情况，avg( question_cnt)
升序排列 group by university order by avg_question_cnt asc
总结得出：
select university , avg( question_cnt) as avg_question_cnt
from user_profile
group by university order by avg_question_cnt asc