Mysql删除表重复记录

Mysql 删除表重复记录，当有多条重复记录时，保存最新记录。

方法一、

delete from IP where ip_id in (select * from (select max(ip_id) as ip_id from IP group by ip_name having count(ip_id)>1) as a)

 

 

方法二、

delete IP as a from IP as a,
(SELECT ip_name,min(ip_id) as ip_id  from IP GROUP BY ip_name having count(ip_name)>1) as b
where a.ip_name = b.ip_name and a.ip_id= b.ip_id