select Selected_Student.student_ID,Selected_Student.name,sum(SCORE.score) as '
总分', avg(SCORE.score) as '平均' from ((select * from STUDENT where grade=1
limit 100) union
(select * from STUDENT where grade=2 limit 100) union
(select * from STUDENT where grade=3 limit 100) union
(select * from STUDENT where grade=4 limit 100) union
(select * from STUDENT where grade=5 limit 100) union
(select * from STUDENT where grade=6 limit 100)) as Selected_Student inner
join SCORE on Selected_Student.student_ID = SCORE.student_ID group by
Selected_Student.student_ID
※ 引述《john9872 (菸酒生)》之铭言：
: 假设我有两个资料表，分别为"学生"及"成绩"，
: 资料字段分别为: ( student_ID, 姓名, 年级 ) 及
: ( 成绩流水号, student_ID, 科目, 分数 )，
: 资料内容如下图例：
: "学生"资料表 "成绩"资料表
:

要乱数的话 " target="_blank" rel="nofollow">