题解 | #分组计算练习题#
分组计算练习题
http://www.nowcoder.com/practice/009d8067d2df47fea429afe2e7b9de45
gender,
university,
count(gender) as user_num,
avg(active_days_within_30) as avg_active_day,
avg(question_cnt) as avg_question_cnt
//函数内的字段不用单独select这个字段
from
user_profile
group by
university,
gender
//以什么来分组
