mysql 删除一张表的重复元素

 由于MySQL无法在同一张表上同时进行删除和查询操作：

解决方案：

建立一张临时表tmpresult：

delete from partno_sup where id in (select id from (select id from partno_sup where partno in 

(select partno from partno_sup group by partno having count(partno)>1) and id not in

(select min(id) from partno_sup group by partno having count(partno)>1)) as tmpresult);

查询一张表的重复元素：

select * from partno_sup where partno in (select partno from partno_sup group by partno having count(partno) > 1)