恢复被rm意外删除数据文件

一.模拟数据文件删除

[oracle@node1 ~]$ sqlplus / as sysdba

 

SQL*Plus: Release 11.2.0.3.0 Production on Sat Dec 31 22:00:52 2011

 

Copyright (c) 1982, 2011, Oracle.  All rights reserved.

 

--数据库版本

Connected to :

Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production

With the Partitioning, Oracle Label Security, OLAP, Data Mining,

Oracle Database Vault and Real Application Testing options

 

--所有数据文件

SQL> select name from v$datafile;

 

NAME

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

/opt/oracle/oradata/ora11g/system01.dbf

/opt/oracle/oradata/ora11g/sysaux01.dbf

/opt/oracle/oradata/ora11g/undotbs01.dbf

/opt/oracle/oradata/ora11g/users01.dbf

/opt/oracle/oradata/ora11g/example01.dbf

 

--删除example01.dbf数据文件

SQL> !rm /opt/oracle/oradata/ora11g/example01.dbf

 

SQL> !ls -l /opt/oracle/oradata/ora11g/example01.dbf

ls: /opt/oracle/oradata/ora11g/example01.dbf: 没有那个文件或目录

 

--因为数据文件被删除，创建表失败

SQL> create table t_xifenfei tablespace example

   2  as select * from dba_tables;

as select * from dba_tables

                  *

ERROR at line 2:

ORA-01116: error in opening database file 5

ORA-01110: data file 5: '/opt/oracle/oradata/ora11g/example01.dbf'

ORA-27041: unable to open file

Linux-x86_64 Error: 2: No such file or directory

Additional information: 3

 

--被删除数据文件离线

SQL> alter database datafile 5 offline;

 

Database altered.

二.找回数据文件

--查找dbw进程spid

[oracle@node1 ~]$ ps -ef| grep dbw| grep - v grep

oracle   18387     1  0 Dec22 ?        00:00:12 ora_dbw0_ora11g

 

--查看该进程所有文件句柄

[oracle@node1 ~]$ ll /proc/18387/fd

总计 0

lr-x------ 1 oracle oinstall 64 12-31 22:03 0 -> /dev/null

l-wx------ 1 oracle oinstall 64 12-31 22:03 1 -> /dev/null

lr-x------ 1 oracle oinstall 64 12-31 22:03 10 -> /dev/zero

lr-x------ 1 oracle oinstall 64 12-31 22:03 11 -> /dev/zero

lr-x------ 1 oracle oinstall 64 12-31 22:03 12 -> /opt/oracle/product/11 .2.0 /db_1/rdbms/mesg/orazhs .msb

lrwx------ 1 oracle oinstall 64 12-31 22:03 13 -> /opt/oracle/product/11 .2.0 /db_1/dbs/hc_ora11g .dat

lr-x------ 1 oracle oinstall 64 12-31 22:03 14 -> /proc/18387/fd

lr-x------ 1 oracle oinstall 64 12-31 22:03 15 -> /dev/zero

lr-x------ 1 oracle oinstall 64 12-31 22:03 16 -> /opt/oracle/product/11 .2.0 /db_1/rdbms/mesg/oraus .msb

lrwx------ 1 oracle oinstall 64 12-31 22:03 17 -> /opt/oracle/product/11 .2.0 /db_1/dbs/hc_ora11g .dat

lrwx------ 1 oracle oinstall 64 12-31 22:03 18 -> /opt/oracle/product/11 .2.0 /db_1/dbs/lkORA11G

lr-x------ 1 oracle oinstall 64 12-31 22:03 19 -> /opt/oracle/product/11 .2.0 /db_1/rdbms/mesg/orazhs .msb

l-wx------ 1 oracle oinstall 64 12-31 22:03 2 -> /dev/null

lr-x------ 1 oracle oinstall 64 12-31 22:03 20 -> /opt/oracle/product/11 .2.0 /db_1/rdbms/mesg/oraus .msb

lrwx------ 1 oracle oinstall 64 12-31 22:03 21 -> socket:[441562]

lrwx------ 1 oracle oinstall 64 12-31 22:03 256 -> /opt/oracle/oradata/ora11g/control01 .ctl

lrwx------ 1 oracle oinstall 64 12-31 22:03 257 -> /opt/oracle/oradata/ora11g/system01 .dbf

lrwx------ 1 oracle oinstall 64 12-31 22:03 258 -> /opt/oracle/oradata/ora11g/sysaux01 .dbf

lrwx------ 1 oracle oinstall 64 12-31 22:03 259 -> /opt/oracle/oradata/ora11g/undotbs01 .dbf

lrwx------ 1 oracle oinstall 64 12-31 22:03 260 -> /opt/oracle/oradata/ora11g/users01 .dbf

lrwx------ 1 oracle oinstall 64 12-31 22:03 261 -> /opt/oracle/oradata/ora11g/example01 .dbf (deleted)

lrwx------ 1 oracle oinstall 64 12-31 22:03 262 -> /opt/oracle/oradata/ora11g/temp01 .dbf

lr-x------ 1 oracle oinstall 64 12-31 22:03 3 -> /dev/null

lr-x------ 1 oracle oinstall 64 12-31 22:03 4 -> /dev/null

lrwx------ 1 oracle oinstall 64 12-31 22:03 5 -> /opt/oracle/product/11 .2.0 /db_1/dbs/hc_ora11g .dat

lr-x------ 1 oracle oinstall 64 12-31 22:03 6 -> /dev/null

lr-x------ 1 oracle oinstall 64 12-31 22:03 7 -> /dev/null

lr-x------ 1 oracle oinstall 64 12-31 22:03 8 -> /dev/null

lr-x------ 1 oracle oinstall 64 12-31 22:03 9 -> /dev/null

--通过句柄恢复数据文件[被删除数据文件会被标示(deleted)]

[oracle@node1 ~]$ cp /proc/18387/fd/261 /opt/oracle/oradata/ora11g/example01 .dbf

--确认该数据文件已经恢复成功

[oracle@node1 ~]$ ll /opt/oracle/oradata/ora11g/example01 .dbf

-rw-r----- 1 oracle oinstall 362422272 12-31 22:05 /opt/oracle/oradata/ora11g/example01 .dbf

三.数据文件online

--恢复数据文件

SQL> recover datafile 5;

Media recovery complete.

 

--数据文件online

SQL> alter database datafile 5 online;

 

Database altered.

 

--创建表测试

SQL> create table t_xifenfei tablespace example

   2  as select * from dba_tables;

 

Table created.

四.补充说明
在意外使用os命令删除掉数据文件时，千万不要慌张重启数据库或者操作系统，可以通过dbwn进程相关句柄找回数据文件

 

如果是unix系统，可能需要先通过lsof找到句柄，然后通过cp实现

[root@node1 ~] # lsof -p 18387 |grep deleted

oracle  18387 oracle  261uW  REG    8,6 362422272   13598733 /opt/oracle/oradata/ora11g/example01 .dbf (deleted)

cd /proc/18387 /fd/

cp 261 /opt/oracle/oradata/ora11g/example01 .dbf