题解 | #分组过滤练习题#
分组过滤练习题
http://www.nowcoder.com/practice/ddbcedcd9600403296038ee44a172f2d
select
university
,avg(question_cnt) avg_question_cnt
,avg(answer_cnt) avg_answer_cnt
from user_profile
group by university
having avg_question_cnt<5
university
,avg(question_cnt) avg_question_cnt
,avg(answer_cnt) avg_answer_cnt
from user_profile
group by university
having avg_question_cnt<5
OR avg_answer_cnt<20
用到having函数,而不是where