这里创建了个表
CREATE TABLE `grade` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(50) NOT NULL,
`grade` varchar(50) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=31 DEFAULT CHARSET=utf8;
select name,sum(grade)/count(1) as gradeArr from grade group by name having gradeArr>80 order by gradeArr desc limit 10;
关键点在group by 分组,having跟where一样,取值