# 取出平均发贴数低于5的学校或平均回帖数小于20的学校
select
university,
avg(question_cnt),
avg(answer_cnt)
from user_profile
group by university
having avg(question_cnt) < 5 or avg(answer_cnt) < 20
; 
# 取出平均发贴数低于5的学校或平均回帖数小于20的学校
select
university,
avg(question_cnt),
avg(answer_cnt)
from user_profile
group by university
having avg(question_cnt) < 5 or avg(answer_cnt) < 20
;