关于对数据库中重复记录的操作

1、如何查询重复的记录，并取出指定的记录？

   select * from Table1 t1 where id in (select max(id) from Table1 t2 where t1.id=t2.id)

2、如何删除记录中重复的数据？

   delete from Table1 where id not in (select id from Table1 t1 where id in (select max(id) from Table1 t2 where t1.id=t2.id))