NAME LOG# THREAD# SEQUENCE# BYTES FIRST_CHANGE# FIRST_TIME TYPE
-------------------------------------------------------------------------------- ---------- ---------- ---------- ---------- ------------- ----------- ---------
/u01/app/fast_recovery_area/ORA11G/flashback/o1_mf_br7bf8xq_.flb 1 1 1 65536000 1350353 19-六月-15 NORMAL
/u01/app/fast_recovery_area/ORA11G/flashback/o1_mf_br7bfdjj_.flb 2 1 1 65536000 0 RESERVED
3、故障发生模拟
下面模拟故障场景，用户test下面有若干段对象。
SQL> select owner, tablespace_name, count(*) from dba_segments where owner='TEST' group by owner, tablespace_name;
OWNER TABLESPACE_NAME COUNT(*)
------------------------------ ------------------------------ ----------
TEST TESTTBL 5
误删除几张数据表。
SQL> drop table test.emp;
Table dropped
SQL> drop table test.dept;
Table dropped
此时数据库SCN和时间信息如下：
SQL> select current_scn, flashback_on from v$database;
CURRENT_SCN FLASHBACK_ON
----------- ------------------
1351835 YES
SQL> select sysdate a from dual;
A
--------------------
19-六月-15 13:54:20
4、恢复操作
下面进行过去test.emp和test.dept数据的寻找。首先，关闭数据库，进行Flashback闪回数据库到未发生故障时间点。
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup mount
ORACLE instance started.
Total System Global Area 372449280 bytes
Fixed Size 1364732 bytes
Variable Size 289410308 bytes
Database Buffers 75497472 bytes
Redo Buffers 6176768 bytes
Database mounted.
直接在mount状态闪回到过去时间点，之后以read only（注意：这个很重要，关系能否回到原点状态）打开数据库。
SQL> flashback database to timestamp to_date('2015-6-19 13:35:00','yyyy-mm-dd hh24:mi:ss');
Flashback complete.
SQL> alter database open read only;
Database altered.
登录闪回版本数据库，查看被删除数据表是否存在。
SQL> conn sys/xxx@ora11g as sysdba
Connected to Oracle Database 11g Enterprise Edition Release 11.2.0.4.0
Connected as SYS
SQL> select owner, tablespace_name, count(*) from dba_segments where owner='TEST' group by owner, tablespace_name;
OWNER TABLESPACE_NAME COUNT(*)
------------------------------ ------------------------------ ----------
TEST TESTTBL 5
下面就清晰很多，可以以数据表（Schema也可以）为目标，导出数据。
[oracle@SimpleLinux ~]$ expdp \"/ as sysdba\" dumpfile=test_part.dmp tables=test.emp,test.dept
Export: Release 11.2.0.4.0 - Production on Fri Jun 19 14:07:38 2015
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining
and Real Application Testing options
ORA-31626: job does not exist
ORA-31633: unable to create master table "SYS.SYS_EXPORT_TABLE_05"
ORA-06512: at "SYS.DBMS_SYS_ERROR", line 95
ORA-06512: at "SYS.KUPV$FT", line 1038
ORA-16000: database open for read-only access
数据泵（Datapump）显然是不行，因为expdp/impdp是工作在后台的数据工具，启动作业起码需要创建一张作业主表。这个对于只读状态数据库显然不行。
退而求其次，使用exp工具，小巧简单。
[oracle@SimpleLinux ~]$ exp \"/ as sysdba\" file=test_part.dmp tables=test.emp,test.dept
Export: Release 11.2.0.4.0 - Production on Fri Jun 19 14:22:33 2015
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining
and Real Application Testing options
Export done in AL32UTF8 character set and AL16UTF16 NCHAR character set
About to export specified tables via Conventional Path ...
Current user changed to TEST
. . exporting table EMP 14 rows exported
. . exporting table DEPT 4 rows exported
Export terminated successfully without warnings.
注意：现在已经成功分离出被误删除的数据，下面可以将数据库恢复到故障恢复点状态。此时，数据库依然是Read Only状态。
SQL> select open_mode from v$database;
OPEN_MODE
--------------------
READ ONLY