begin tran delete from WxUser_BMUser where OpenId in ( select a.OpenId from WxUser_BMUser a where IsUnBind=0 group by a.OpenId having COUNT(1)>1 ) and id not in (select min(id) from WxUser_BMUser where IsUnBind=0 group by OpenId having count(1)>1) rollback commit
原文：http://www.cnblogs.com/yangjinwang/p/7279392.html