要求:查看不同大学的用户平均发帖情况,并期望结果按照平均发帖情况进行升序排列
1.(不同大学)分组 group by
2.(平均发帖)avg()
3.(升序排列)order by 平均发帖 asc
select university ,avg(question_cnt) as avg_question_cnt
from user_profile
group by university
order by avg_question_cnt asc