Flashback table ORA-01466: unable to read data table definition has changed

SQL> show user
USER is "HN"

SQL> select * from emp;  //查询hn.emp表

SQL> select to_char(sysdate, 'yyyy-mm-dd:HH24:MI:SS') from dual; //查看时间

SQL> truncate table hn.emp;  //将hn.emp表中的数据truncate掉

//开启hn.emp表的row movment功能
SQL> alter table hn.emp enable row movement;
SQL> select table_name, user_tables.row_movement from user_tables from user_tables;

SQL> flashback table to timestamp to_timestamp('2015-01-24:03:34:45', 'yyyy-mm-dd:HH24:MI:SS');

--ORA-01466: unable to read data - table definition has changed
总结：
    flashback table功能依赖于UNDO数据，虽然ddl语句差生redo 和undo信息，但是，flashback table 不能跨ddl进行闪回
    对于ddl的闪回只能使用flashback database功能