題解 | #計(jì)算男生人數(shù)以及平均GPA#
計(jì)算男生人數(shù)以及平均GPA
http://www.fangfengwang8.cn/practice/7d9a7b2d6b4241dbb5e5066d7549ca01
SELECT count(gender) as male_num,avg(gpa) as avg_gpa from user_profile where gender = 'male'
像這樣聚合函數(shù)和聚合函數(shù)之間用,隔開,不要用and