参考:http://wenku.baidu.com/view/956085bbc77da26925c5b0a9.html
select object_name,original_name,partition_name,type,ts_name,createtime,droptime from recyclebin;
flashback table sms_user to before drop;
select object_name,original_name,partition_name,type,ts_name,createtime,droptime from recyclebin;
flashback table sms_user to before drop;