MYSQL怎么删除重复的数据

如下图，如果L_ListingID和photo这两列有重复的，我用下面的SQL执行更新删除重复的，MYSQL直接挂掉了，请教应该如何正确的删除数据库里所有重复的。

DELETE e1 FROM www_photo e1, www_photo e2 WHERE e1.photo = e2.photo AND e1.photoid > e2.photoid;

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DELETE e1 FROM www_photo e1 INNER JOIN(SELECT e.photo,e.photoid FROM www_photo e)e2 ON(e1.photo = e2.photo AND e1.photoid > e2.photoid);

这样可以吗？

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查找出来倒是可以，mysql5.5测试时select换成delete报错了

select * from  www_photo
where photo in (select photo from www_photo group by photo having count(photo) > 1) 
and photoid not in (select min(photoid) from  www_photo group by photo having count(photo)>1) 

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把photo字段加上索引，如果有其他想法后续更新