[Quote=引用 2 楼 WWWWA 的回复:]
没有看到记录及要求结果,TRY:
SELECT A.student_id,A.class_id,A.score
FROM TT A LEFT JOIN TT B
ON A.class_id=B.class_id AND A.SCORE <=B.SCORE
GROUP BY A.student_id,A.class_id,A.score
HAVING COUNT(B.class_id) <=2
[/Quote]
大哥的SQL果然强悍。。。。。
没有看到记录及要求结果,TRY:
SELECT A.student_id,A.class_id,A.score
FROM TT A LEFT JOIN TT B
ON A.class_id=B.class_id AND A.SCORE<=B.SCORE
GROUP BY A.student_id,A.class_id,A.score
HAVING COUNT(B.class_id)<=2