select *
from A
where id in (select id from A group by id having count(1) >= 2)
注释：id 为重复的关键字（更换成所需要的）
开发实例：
select CarlotName ,CheweiID
from Position_Car a
where a.CarlotName in (select CarlotName from Position_Car b group by b.CarlotName having count(1) >= 2)
原文：http://www.cnblogs.com/tuhong/p/5719125.html