1） 找到重复的记录，归类到一个新表里面 max(id) 是想要删除的record
create table ttt as select gallery_url ,max(id) as theid from gallery group by gallery_url having count(*) >=2
2） 删除
delete from gallery where id in ( select theid from ttt)
原文：https://www.cnblogs.com/johnsonshu/p/11710938.html