Oracle数据库中数据文件误删除的恢复

环境说明：

• 数据库处于归档模式
• 数据库文件或表空间无备份
• 数据库的归档日志全部存在(数据文件丢失之后)

模拟状态：

• 数据文件丢失及时发现，实例处于运行状态
• 数据文件丢失未及时发现，实例自检时异常关闭

---

数据文件丢失及时发现，实例处于运行状态

1.创建实验表空间

sys@DBTREE> create tablespace tbs_d datafile '/u01/app/oracle/oradata/dbtree/tbs_d01.dbf' size 20M autoextend on next 20M;

Tablespace created.

sys@DBTREE> create user u_tbs_d identified by 1 default tablespace tbs_d quota unlimited on tbs_d;

User created.

sys@DBTREE> grant connect,resource to u_tbs_d;

Grant succeeded.

sys@DBTREE> conn u_tbs_d/1
Connected.
u_tbs_d@DBTREE> create table tab_t (v_num int);

Table created.

u_tbs_d@DBTREE> begin
  2  for x in 1..10000 loop
  3  insert into tab_t values (x);
  4  end loop;
  5  commit;
  6  end;
  7  /

PL/SQL procedure successfully completed.

u_tbs_d@DBTREE> select count(1) from tab_t;

  COUNT(1)
----------
     10000

u_tbs_d@DBTREE> select * from tab_t where rownum < 10;

     V_NUM
----------
       661
       662
       663
       664
       665
       666
       667
       668
       669

9 rows selected.

2.删除新创建的表空间对应的数据文件

[oracle@zabbix dbtree]$ ls
control01.ctl  redo01.log  redo02.log  redo03.log  sysaux01.dbf  system01.dbf  tbs_d01.dbf  temp01.dbf  undotbs01.dbf  users01.dbf  zabbix01.dbf
[oracle@zabbix dbtree]$ pwd
/u01/app/oracle/oradata/dbtree
[oracle@zabbix dbtree]$ rm -f tbs_d01.dbf
[oracle@zabbix dbtree]$ ls
control01.ctl  redo01.log  redo02.log  redo03.log  sysaux01.dbf  system01.dbf  temp01.dbf  undotbs01.dbf  users01.dbf  zabbix01.dbf


u_tbs_d@DBTREE> select count(1) from tab_t;

  COUNT(1)
----------
     10000

u_tbs_d@DBTREE> create table tab_t02 as select * from tab_t;
create table tab_t02 as select * from tab_t
                                      *
ERROR at line 1:
ORA-01116: error in opening database file 6
ORA-01110: data file 6: '/u01/app/oracle/oradata/dbtree/tbs_d01.dbf'
ORA-27041: unable to open file
Linux-x86_64 Error: 2: No such file or directory
Additional information: 3

3.通过Linux句柄恢复数据文件

系统层面操作
[oracle@zabbix dbtree]$ ps -ef | grep dbw
oracle   31532     1  0 14:44 ?        00:00:00 ora_dbw0_dbtree
oracle   37263 31440  0 16:06 pts/2    00:00:00 grep --color=auto dbw
[oracle@zabbix dbtree]$ ll /proc/31532/fd
total 0
lr-x------ 1 oracle oinstall 64 Jun 26 16:06 0 -> /dev/null
l-wx------ 1 oracle oinstall 64 Jun 26 16:06 1 -> /dev/null
lrwx------ 1 oracle oinstall 64 Jun 26 16:06 10 -> /u01/app/oracle/product/11.2.0.4/dbhome_1/dbs/lkDBTREE
lr-x------ 1 oracle oinstall 64 Jun 26 16:06 13 -> /u01/app/oracle/product/11.2.0.4/dbhome_1/rdbms/mesg/oraus.msb
lrwx------ 1 oracle oinstall 64 Jun 26 16:06 14 -> socket:[1507933]
l-wx------ 1 oracle oinstall 64 Jun 26 16:06 2 -> /dev/null
lrwx------ 1 oracle oinstall 64 Jun 26 16:06 256 -> /u01/app/oracle/oradata/dbtree/control01.ctl
lrwx------ 1 oracle oinstall 64 Jun 26 16:06 257 -> /u01/app/oracle/fast_recovery_area/dbtree/control02.ctl
lrwx------ 1 oracle oinstall 64 Jun 26 16:06 258 -> /u01/app/oracle/oradata/dbtree/system01.dbf
lrwx------ 1 oracle oinstall 64 Jun 26 16:06 259 -> /u01/app/oracle/oradata/dbtree/sysaux01.dbf
lrwx------ 1 oracle oinstall 64 Jun 26 16:06 260 -> /u01/app/oracle/oradata/dbtree/undotbs01.dbf
lrwx------ 1 oracle oinstall 64 Jun 26 16:06 261 -> /u01/app/oracle/oradata/dbtree/users01.dbf
lrwx------ 1 oracle oinstall 64 Jun 26 16:06 262 -> /u01/app/oracle/oradata/dbtree/zabbix01.dbf
lrwx------ 1 oracle oinstall 64 Jun 26 16:06 263 -> /u01/app/oracle/oradata/dbtree/tbs_d01.dbf (deleted)
lrwx------ 1 oracle oinstall 64 Jun 26 16:06 264 -> /u01/app/oracle/oradata/dbtree/temp01.dbf
lr-x------ 1 oracle oinstall 64 Jun 26 16:06 3 -> /dev/null
lr-x------ 1 oracle oinstall 64 Jun 26 16:06 4 -> /dev/null
lr-x------ 1 oracle oinstall 64 Jun 26 16:06 5 -> /dev/null
lr-x------ 1 oracle oinstall 64 Jun 26 16:06 6 -> /u01/app/oracle/product/11.2.0.4/dbhome_1/rdbms/mesg/oraus.msb
lr-x------ 1 oracle oinstall 64 Jun 26 16:06 7 -> /proc/31532/fd
lr-x------ 1 oracle oinstall 64 Jun 26 16:06 8 -> /dev/zero
lrwx------ 1 oracle oinstall 64 Jun 26 16:06 9 -> /u01/app/oracle/product/11.2.0.4/dbhome_1/dbs/hc_dbtree.dat
[oracle@zabbix dbtree]$ cp /proc/31532/fd/263 /u01/app/oracle/oradata/dbtree/tbs_d01.dbf
[oracle@zabbix dbtree]$ ll
total 3568812
-rw-r----- 1 oracle oinstall    9748480 Jun 26 16:06 control01.ctl
-rw-r----- 1 oracle oinstall   52429312 Jun 26 14:47 redo01.log
-rw-r----- 1 oracle oinstall   52429312 Jun 26 16:06 redo02.log
-rw-r----- 1 oracle oinstall   52429312 Jun 26 14:47 redo03.log
-rw-r----- 1 oracle oinstall 1073750016 Jun 26 16:06 sysaux01.dbf
-rw-r----- 1 oracle oinstall 1073750016 Jun 26 16:06 system01.dbf
-rw-r----- 1 oracle oinstall   20979712 Jun 26 16:06 tbs_d01.dbf
-rw-r----- 1 oracle oinstall   30416896 Jun 25 22:00 temp01.dbf
-rw-r----- 1 oracle oinstall 1073750016 Jun 26 16:05 undotbs01.dbf
-rw-r----- 1 oracle oinstall  136323072 Jun 26 14:47 users01.dbf
-rw-r----- 1 oracle oinstall  104865792 Jun 26 14:47 zabbix01.dbf

数据库层面操作

sys@DBTREE> @chkdbf     

TABLESPACE_NAME         FILE_ID FILE_NAME                                                  MB      MAXMB AUT STATUS               ONLINE_
-------------------- ---------- -------------------------------------------------- ---------- ---------- --- -------------------- -------
SYSTEM                        1 /u01/app/oracle/oradata/dbtree/system01.dbf              1024      32768 YES AVAILABLE            SYSTEM
SYSAUX                        2 /u01/app/oracle/oradata/dbtree/sysaux01.dbf              1024      32768 YES AVAILABLE            ONLINE
UNDOTBS1                      3 /u01/app/oracle/oradata/dbtree/undotbs01.dbf             1024      32768 YES AVAILABLE            ONLINE
USERS                         4 /u01/app/oracle/oradata/dbtree/users01.dbf                130      32768 YES AVAILABLE            ONLINE
ZABBIX                        5 /u01/app/oracle/oradata/dbtree/zabbix01.dbf               100      32768 YES AVAILABLE            ONLINE
TBS_D                         6 /u01/app/oracle/oradata/dbtree/tbs_d01.dbf                 20      32768 YES AVAILABLE            ONLINE

6 rows selected.

sys@DBTREE> alter database datafile 6 offline;

Database altered.

sys@DBTREE> recover datafile 6;
Media recovery complete.
sys@DBTREE> alter database datafile 6 online;

Database altered.

sys@DBTREE> conn u_tbs_d/1
Connected.

u_tbs_d@DBTREE> select count(1) from tab_t;

  COUNT(1)
----------
     10000

u_tbs_d@DBTREE> create table tab_t02 as select * from tab_t;

Table created.

u_tbs_d@DBTREE> select count(1) from tab_t02;

  COUNT(1)
----------
     10000

到此步骤，数据文件恢复完成

---

数据文件丢失未及时发现，实例自检时异常关闭

1.创建实验表空间

此步骤和上一种类型一致，不在赘述

2.删除新创建的表空间对应的数据文件

此步骤和上一种类型一致，不在赘述

3.模拟实例自检时数据库异常关闭

sys@DBTREE> alter system switch logfile;

System altered.

sys@DBTREE> /

System altered.

sys@DBTREE> /
ERROR:
ORA-03114: not connected to ORACLE

alter system switch logfile
*
ERROR at line 1:
ORA-03113: end-of-file on communication channel
Process ID: 38296
Session ID: 96 Serial number: 21

[oracle@zabbix dbtree]$ ps -ef | grep ora_
oracle   38404 31440  0 16:22 pts/2    00:00:00 grep --color=auto ora_

4.利用归档日志文件重建文件

idle> startup mount;
ORACLE instance started.

Total System Global Area 2137886720 bytes
Fixed Size          2254952 bytes
Variable Size         587204504 bytes
Database Buffers     1543503872 bytes
Redo Buffers            4923392 bytes
Database mounted.
idle> alter database create datafile 6;

Database altered.

idle> recover datafile 6;
Media recovery complete.
idle> alter database open;

Database altered.

idle> conn u_tbs_d/1
Connected.
u_tbs_d@DBTREE> select count(1) from tab_t;

  COUNT(1)
----------
     10000

u_tbs_d@DBTREE> create table tab_t02 as select * from tab_t;

Table created.

u_tbs_d@DBTREE> select count(1) from tab_t02;

  COUNT(1)
----------
     10000

到此步骤，数据文件恢复完成