select * from people where peopleId in (select peopleId from people group by peopleId having count(peopleId) > 1)
http://www.codesky.net/article/201011/146964.html
MYSQL查询重复记录的方法,布布扣,bubuko.com
MYSQL查询重复记录的方法
原文：http://www.cnblogs.com/kyxyes/p/3598178.html
