题解 | #计算男生人数以及平均GPA#
计算男生人数以及平均GPA
http://www.nowcoder.com/practice/7d9a7b2d6b4241dbb5e5066d7549ca01
select count(gender) as male_num,
round(avg(gpa), 1) as avg_gpa
from user_profile
where gender = "male";
count 是计数函数,自带 round 可以指定小数点位数, avg 为求平均函数