SELECT
  student.name 学生,
  course.name 科目,
  mscore.score 成绩
FROM (SELECT *
      FROM SCORE OSCORE
      WHERE (SELECT
               COUNT(*)
             FROM SCORE ISCORE
             WHERE ISCORE.COURSE_ID = OSCORE.COURSE_ID
                 AND ISCORE.SCORE > OSCORE.SCORE) < 3
      ORDER BY OSCORE.COURSE_ID,OSCORE.SCORE DESC) mscore,
  student,
  course
WHERE student.student_id = mscore.student_id
    AND course.course_id = mscore.course_id