分享到： ------解决方案-------------------- 童鞋，给你一句忠告以后再设计sql时应注意，避免让数据库为你计算，这样会让系统变得很慢，数据量大的时候还可能导致数据库服务器的down机。sql中有orderby 和 groupby这两个可以解决你的问题。自己上网上查下怎么用 ------解决方案-------------------- select a.学号,b.姓名,b.性别, sum(a.成绩)/(select coun(*) from 成绩表 ) as 平均成绩
from 成绩表 a left join 学生表 b
on a.学号 =b.学号
group by a.学号
order by sum(a.成绩) asc ------解决方案-------------------- select 学号, sum(成绩) as 总成绩, avg(成绩) as 平均成绩 from 成绩表 group by 1 order by 4
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