此方法适用于近期DELETE的数据
select to_char(sysdate,'yyyy-mm-dd hh24:mi:ss') from dual;
select * from 用户名.表名 as of timestamp to_timestamp('2017-08-31 15:35:39','yyyy-mm-dd hh24:mi:ss');alter table 用户名.表名 enable row movement;
flashback table 用户名.表名 to timestamp to_timestamp('2017-08-31 15:35:39','yyyy-mm-dd hh24:mi:ss');