delete a from yourTable a,yourTable b where a.id=b.id and a.a>b.a;

------解决方案--------------------


这种情况，两条记录所有字段相同，没有办法进行删除！
只能

select distinct * from yourTable  
得到一个不重复的。然后清空原表。

可以

create table tttt as select distinct * from yourTable ;
delete from yourTable ;
insert into yourTable select * from ttt;


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