提取表中每个分组的前几条数据

提取表中每个分组的前几条数据 SELECT 课程, SUM(奖金) AS 奖金 FROM ( SELECT 课程, 学号, 成绩 FROM 考试 AS a WHERE ( SELECT COUNT(*) FROM 考试 WHERE 课程 = a.课程 AND 学号 a.学号 AND 成绩 a.成绩 ) 3 www.2cto.com ) AS b GROUP BY 课程

提取表中每个分组的前几条数据

SELECT 课程,

SUM(奖金) AS 奖金

FROM ( SELECT 课程,

学号,

成绩

FROM 考试 AS a

WHERE ( SELECT COUNT(*)

FROM 考试

WHERE 课程 = a.课程

AND 学号 a.学号

AND 成绩 > a.成绩

)

) AS b

GROUP BY 课程