FTP 命令详解

前提，数据库处于archivelog mode

场景如下：

1.开启flashback
SQL> startup mount

ORACLE instance started.

Total System Global Area 536870912 bytes

Fixed Size 1262812 bytes

Variable Size 520096548 bytes

Database Buffers 12582912 bytes

Redo Buffers 2928640 bytes

Database mounted.

SQL>

SQL>

SQL> select flashback_on from v$database;

FLASHBACK_ON

------------------

NO

SQL> alter database flashback on;

Database altered.

SQL> select flashback_on from v$database;

FLASHBACK_ON

------------------

YES
 

2. 准备试验数据
create tablespace test_rman_bak datafile '/oracle/oradata/monster/test_rman_bak.dbf' size 10M;

create user zhanglei identified by zhanglei default tablespace test_rman_bak;

grant dba to zhanglei;

conn zhanglei/zhanglei

create table A1

(id number(3),

name varchar2(20)

)

/

SQL> select * from zhanglei.a1;

        ID NAME

---------- --------------------

         1 test1

         2 test2

         3 test3

 
3.手动删除一个tablespace

--记录下删除前的SCN

SQL> select current_scn from v$database;

CURRENT_SCN

-----------

8.7961E+12

SQL> col current_scn for 9999999999999

SQL> /

CURRENT_SCN

--------------

8796117159141

SQL> drop tablespace TEST_RMAN_BAK including contents and datafiles;

Tablespace dropped.
 
4.尝试直接flashback，看看结果如何
SQL> conn / as sysdba

Connected.

SQL> shutdown immediate

Database closed.

Database dismounted.

ORACLE instance shut down.

SQL> startup mount

ORACLE instance started.

Total System Global Area 536870912 bytes

Fixed Size 1262812 bytes

Variable Size 520096548 bytes

Database Buffers 12582912 bytes

Redo Buffers 2928640 bytes

Database mounted.

SQL> select name from v$datafile;

NAME

--------------------------------------------------------------------------------

/oracle/oradata/monster/system01.dbf

/oracle/oradata/monster/pwrcard01.dbf

/oracle/oradata/monster/sysaux01.dbf

/oracle/oradata/monster/users01.dbf

/oracle/oradata/monster/logmnrts.dbf

/oracle/oradata/monster/tools.dbf

/oracle/oradata/monster/testcdc.dbf

/oracle/oradata/monster/undotbs01.dbf

/oracle/oradata/monster/rman.dbf

9 rows selected.

SQL> flashback database to scn 8796117159141;

flashback database to scn 8796117159141

*

ERROR at line 1:

ORA-38795: warning: FLASHBACK succeeded but OPEN RESETLOGS would get error

below

ORA-01245: offline file 10 will be lost if RESETLOGS is done

ORA-01111: name for data file 10 is unknown - rename to correct file

ORA-01110: data file 10: '/oracle/product/10.2.0/db_1/dbs/UNNAMED00010'

SQL> alter database open resetlogs;

alter database open resetlogs

*

ERROR at line 1:

ORA-01245: offline file 10 will be lost if RESETLOGS is done

ORA-01110: data file 10: '/oracle/oradata/monster/test_rman_bak.dbf'
 
5.手动建一个datafile,然后再次flashback

--从下面的结果可以看到，虽然上次的flashback没有成功完成，但是他却为我们生成了一个datafile

SQL> select name from v$datafile;

NAME

--------------------------------------------------------------------------------

/oracle/oradata/monster/system01.dbf

/oracle/oradata/monster/pwrcard01.dbf

/oracle/oradata/monster/sysaux01.dbf

/oracle/oradata/monster/users01.dbf

/oracle/oradata/monster/logmnrts.dbf

/oracle/oradata/monster/tools.dbf

/oracle/oradata/monster/testcdc.dbf

/oracle/oradata/monster/undotbs01.dbf

/oracle/oradata/monster/rman.dbf
/oracle/product/10.2.0/db_1/dbs/UNNAMED00010

10 rows selected.

--用[alter database create datafile as]重建被删除的datafile

SQL> alter database create datafile '/oracle/product/10.2.0/db_1/dbs/UNNAMED00010' as '/oracle/oradata/monster/test_rman_bak.dbf';

Database altered.

SQL> select name from v$datafile;

NAME

--------------------------------------------------------------------------------

/oracle/oradata/monster/system01.dbf

/oracle/oradata/monster/pwrcard01.dbf

/oracle/oradata/monster/sysaux01.dbf

/oracle/oradata/monster/users01.dbf

/oracle/oradata/monster/logmnrts.dbf

/oracle/oradata/monster/tools.dbf

/oracle/oradata/monster/testcdc.dbf

/oracle/oradata/monster/undotbs01.dbf

/oracle/oradata/monster/rman.dbf

/oracle/oradata/monster/test_rman_bak.dbf

10 rows selected.

--flashback成功完成

SQL> flashback database to scn 8796117159141;

Flashback complete.

SQL> alter database open;

alter database open

*

ERROR at line 1:

ORA-01589: must use RESETLOGS or NORESETLOGS option for database open

--数据库正常打开

SQL> alter database open resetlogs;

Database altered.
 
6.确认实验数据是否被成功恢复
SQL> select * from zhanglei.a1;

        ID NAME

---------- --------------------

         1 test1

         2 test2

         3 test3