oracle db在omf自动管理文件下并在文件存放在ASM里,如果手工rename 一个文件OMF文件,oracle会自动删除原有文件,以下是测试 SQL SELECT file#,name FROM v$datafile; FILE# NAME---------- ----------------------------------------------------------------
oracle db在omf自动管理文件下并在文件存放在ASM里,如果手工rename 一个文件OMF文件,oracle会自动删除原有文件,以下是测试
SQL> SELECT file#,name FROM v$datafile;
FILE# NAME
---------- --------------------------------------------------------------------------------
1 +ASMDATA/racdb/datafile/system.256.814462679
2 +ASMDATA/racdb/datafile/sysaux.257.814462681
3 +ASMDATA/racdb/datafile/undotbs1.258.814462681
4 +ASMDATA/racdb/datafile/users.259.814462681
5 +ASMDATA/racdb/datafile/undotbs2.264.814462949
6 +ASMDATA/racdb/datafile/test.268.815753637
7 +ASMDATA/racdb/datafile/goldengate.341.820339679
8 +ASMDATA/racdb/datafile/ccdata.375.844202017
9 +ASMDATA/racdb/datafile/soe.460.844203543
10 +ASMDATA/racdb/datafile/big_test.661.852999379
10 ROWS selected.
这里先通过rman backup as copy 备份一个文件
[oracle@rac1 ~]$ rman target / Recovery Manager: Release 11.2.0.3.0 - Production ON Fri Jul 18 11:59:24 2014 Copyright (c) 1982, 2011, Oracle AND/OR its affiliates. ALL rights reserved. connected TO target DATABASE: RACDB (DBID=812079559) RMAN> backup AS copy datafile 10 format '+ASMDATA/racdb/datafile/big_test01.dbf'; Starting backup at 18-JUL-14 USING target DATABASE control file instead OF recovery catalog allocated channel: ORA_DISK_1 channel ORA_DISK_1: SID=76 instance=racdb1 device TYPE=DISK channel ORA_DISK_1: starting datafile copy INPUT datafile file NUMBER=00010 name=+ASMDATA/racdb/datafile/big_test.661.852999379 output file name=+ASMDATA/racdb/datafile/big_test01.dbf tag=TAG20140718T115951 RECID=4 STAMP=853243196 channel ORA_DISK_1: datafile copy complete, elapsed TIME: 00:00:08 Finished backup at 18-JUL-14 RMAN>
[grid@rac1 ~]$ asmcmd
ls -lASMCMD>
State TYPE Rebal Name
MOUNTED EXTERN N ASMDATA/
MOUNTED EXTERN N DATA/
ASMCMD> ASMCMD>
ASMCMD> ls -l +ASMDATA/racdb/datafile/big_test01.dbf
TYPE Redund Striped TIME Sys Name
N big_test01.dbf => +ASMDATA/RACDB/DATAFILE/BIG_TEST.664.853243193
ASMCMD> ls -l +ASMDATA/racdb/datafile/big_test.661.852999379
TYPE Redund Striped TIME Sys Name
DATAFILE UNPROT COARSE JUL 18 11:00:00 Y big_test.661.852999379
ASMCMD> ls -l +ASMDATA/racdb/datafile/big_test*
TYPE Redund Striped TIME Sys Name
DATAFILE UNPROT COARSE JUL 18 11:00:00 Y BIG_TEST.661.852999379
DATAFILE UNPROT COARSE JUL 18 11:00:00 Y BIG_TEST.664.853243193
N big_test01.dbf => +ASMDATA/RACDB/DATAFILE/BIG_TEST.664.853243193
这里直切swtich datafile 看下
RMAN> switch datafile 10 TO copy;
USING target DATABASE control file instead OF recovery catalog
datafile 10 switched TO datafile copy "+ASMDATA/racdb/datafile/big_test01.dbf"
RMAN> recover datafile 10;
Starting recover at 18-JUL-14
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=80 instance=racdb1 device TYPE=DISK
starting media recovery
media recovery complete, elapsed TIME: 00:00:02
Finished recover at 18-JUL-14
RMAN> SQL 'alter database datafile 10 online';
SQL statement: ALTER DATABASE datafile 10 online
ASMCMD> ls -l +ASMDATA/racdb/datafile/big_test*
TYPE Redund Striped TIME Sys Name
DATAFILE UNPROT COARSE JUL 18 12:00:00 Y BIG_TEST.661.852999379
DATAFILE UNPROT COARSE JUL 18 12:00:00 Y BIG_TEST.664.853243193
N big_test01.dbf => +ASMDATA/RACDB/DATAFILE/BIG_TEST.664.853243193
从这里在看两个文件都存在,所以说在文件OMF命名格式下，rman的switch datafile 不会删除文件
下面看下在sqlplus下直接rename
SQL> ALTER DATABASE datafile 10 offline; DATABASE altered. SQL> SQL> ALTER DATABASE RENAME file '+ASMDATA/racdb/datafile/big_test01.dbf' TO '+ASMDATA/racdb/datafile/big_test.661.852999379'; DATABASE altered. SQL> recover datafile 10; Media recovery complete. SQL> ALTER DATABASE datafile 10 online; DATABASE altered. Completed: ALTER DATABASE RENAME file '+ASMDATA/racdb/datafile/big_test01.dbf' TO '+ASMDATA/racdb/datafile/big_test.661.852999379' Fri Jul 18 12:08:21 2014 ALTER DATABASE RECOVER datafile 10 Media Recovery START Serial Media Recovery started WARNING! Recovering DATA file 10 FROM a fuzzy backup. It might be an online backup taken WITHOUT entering the BEGIN backup command. Recovery OF Online Redo Log: Thread 1 GROUP 2 Seq 337 Reading mem 0 Mem# 0: +ASMDATA/racdb/onlinelog/group_2.262.814462797 Media Recovery Complete (racdb1) Completed: ALTER DATABASE RECOVER datafile 10 ALTER DATABASE datafile 10 online Completed: ALTER DATABASE datafile 10 onlin
ASMCMD> ls -l +ASMDATA/racdb/datafile/big_test*
Type Redund Striped Time Sys Name
DATAFILE UNPROT COARSE JUL 18 12:00:00 Y BIG_TEST.661.852999379
DATAFILE UNPROT COARSE JUL 18 12:00:00 Y BIG_TEST.664.853243193
N big_test01.dbf => +ASMDATA/RACDB/DATAFILE/BIG_TEST.664.853243193
这里看到从手工命令的文件切换到OMF命令的文件，原文件也没用被删除。
看下omf切换到手工命令文件
SQL> ALTER DATABASE datafile 10 offline; DATABASE altered. SQL> ALTER DATABASE RENAME file '+ASMDATA/racdb/datafile/big_test.661.852999379' TO '+ASMDATA/racdb/datafile/big_test01.dbf'; DATABASE altered. SQL> recover datafile 10; Media recovery complete. SQL> ALTER DATABASE datafile 10 online; DATABASE altered.
alter日志文件如下
alter database rename file '+ASMDATA/racdb/datafile/big_test.661.852999379' to '+ASMDATA/racdb/datafile/big_test01.dbf' Deleted Oracle managed file +ASMDATA/racdb/datafile/big_test.661.852999379 Completed: alter database rename file '+ASMDATA/racdb/datafile/big_test.661.852999379' to '+ASMDATA/racdb/datafile/big_test01.dbf' Fri Jul 18 12:12:35 2014
明显看出文件被delete ,Deleted Oracle managed file
ASMCMD> ls -l +ASMDATA/racdb/datafile/big_test*
Type Redund Striped Time Sys Name
DATAFILE UNPROT COARSE JUL 18 12:00:00 Y BIG_TEST.664.853243193
N big_test01.dbf => +ASMDATA/RACDB/DATAFILE/BIG_TEST.664.853243193
从asmcmd看到只剩下一个文件
原文地址：Oracle Db Rname datafile/redofile on ASM, 感谢原作者分享。
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