Question: I want to re-name my
database to change the ORACLE_SID value. I have changed the
instance_name parameter in parameter file also but its still at database
said showing same when we select instance_name from v$instance?
What is the proper way to re-name an Oracle instance?
Answer: To completely re-name a
database you need to change all of the components where the instance name is
located:
-
External files: sqlnet.ora, tnsnames.ora,
init.ora (spfile)
-
Internal locations: Data dictionary
Here are the "traditional" steps to re-name an
Oracle database (note new procedure for renaming an instance in 9i and beyond
later on this page):
STEP 1: On the old system, go into SQL*Plus, sign on as SYSDBA and
issue: “alter database backup controlfile to trace”. This will put the create
database syntax in the trace file directory. The trace keyword tells oracle to
generate a script containing a create controlfile command and store it in the
trace directory identified in the user_dump_dest parameter of the init.ora file.
It will look something like this:
STARTUP NOMOUNT
CREATE CONTROLFILE REUSE DATABASE "OLDLSQ" NORESETLOGS
NOARCHIVELOG
MAXLOGFILES 16
MAXLOGMEMBERS 2
MAXDATAFILES 240
MAXINSTANCES 1
MAXLOGHISTORY 113
LOGFILE
GROUP 1 ('/u03/oradata/oldlsq/log1a.dbf',
'/u03/oradata/olslsq/log1b.dbf') SIZE 30M,
GROUP 2 ('/u04/oradata/oldlsq/log2a.dbf',
'/u04/oradata/oldlsq/log2b.dbf') SIZE 30M
DATAFILE
'/u01/oradata/oldlsq/system01.dbf',
'/u01/oradata/oldlsq/mydatabase.dbf'
;
# Recovery is required if any of the datafiles are restored
# backups, or if the last shutdown was not normal or immediate.
RECOVER DATABASE
# Database can now be opened normally.
ALTER DATABASE OPEN;
STEP 2: Shutdown the old database
STEP 3: Change all references to the old instance
name in all locations for sqlnet.ora, protocol.ora, tnsnames.ora and the
init.ora (or spfile for the database).
STEP 4: Change the database name in the file to
reference the new ORACLE_SID instance name:
STARTUP NOMOUNT
CREATE CONTROLFILE REUSE DATABASE "NEWLSQ" NORESETLOGS
NOARCHIVELOG
MAXLOGFILES 16
MAXLOGMEMBERS 2
MAXDATAFILES 240
MAXINSTANCES 1
MAXLOGHISTORY 113
LOGFILE
GROUP 1 ('/u03/oradata/newlsq/log1a.dbf',
'/u03/oradata/newlsq/log1b.dbf') SIZE 30M,
GROUP 2 ('/u04/oradata/newlsq/log2a.dbf',
'/u04/oradata/newlsq/log2b.dbf') SIZE 30M
DATAFILE
'/u01/oradata/newlsq/system01.dbf',
'/u01/oradata/newlsq/mydatabase.dbf'
;
# Re-named database can now be opened normally.
ALTER DATABASE OPEN RESETLOGS;
ALTER TABLESPACE TEMP ADD TEMPFILE ''/u04/oradata/newlsq/log2a.dbf/temp.dbf'
SIZE 104857600 REUSE AUTOEXTEND OFF;
A new method for a database rename instance
For Oracle9i and beyond, Oracle author
Dr. Tim Hall
has this procedure
to rename an Oracle database using the new dbnewid (also called nid,
for new ID) utility:
- STEP 1: Backup the database.
- STEP 2: Mount the database after a clean shutdown:
SHUTDOWN IMMEDIATE
STARTUP MOUNT
- STEP 3: Invoke the DBNEWID utility (nid)
specifying the new DBNAME from the command line using a user with
SYSDBA privilege:
nid TARGET=sys/password@TSH1 DBNAME=TSH2
Assuming the validation is successful the utility prompts for
confirmation before performing the actions. Typical output may look
something like:
C:\oracle\920\bin>nid TARGET=sys/password@TSH1 DBNAME=TSH2
DBNEWID: Release 9.2.0.3.0 - Production
Copyright (c) 1995, 2002, Oracle Corporation. All rights reserved.
Connected to database TSH1 (DBID=1024166118)
Control Files in database:
C:\ORACLE\ORADATA\TSH1\CONTROL01.CTL
C:\ORACLE\ORADATA\TSH1\CONTROL02.CTL
C:\ORACLE\ORADATA\TSH1\CONTROL03.CTL
Change database ID and database name TSH1 to TSH2? (Y/[N]) => Y
Proceeding with operation
Changing database ID from 1024166118 to 1317278975
Changing database name from TSH1 to TSH2
Control File C:\ORACLE\ORADATA\TSH1\CONTROL01.CTL - modified
Control File C:\ORACLE\ORADATA\TSH1\CONTROL02.CTL - modified
Control File C:\ORACLE\ORADATA\TSH1\CONTROL03.CTL - modified
Datafile C:\ORACLE\ORADATA\TSH1\SYSTEM01.DBF - dbid changed, wrote new name
Datafile C:\ORACLE\ORADATA\TSH1\UNDOTBS01.DBF - dbid changed, wrote new name
Datafile C:\ORACLE\ORADATA\TSH1\CWMLITE01.DBF - dbid changed, wrote new name
Control File C:\ORACLE\ORADATA\TSH1\CONTROL01.CTL - dbid changed, wrote new name
Control File C:\ORACLE\ORADATA\TSH1\CONTROL02.CTL - dbid changed, wrote new name
Control File C:\ORACLE\ORADATA\TSH1\CONTROL03.CTL - dbid changed, wrote new name
Database name changed to TSH2.
Modify parameter file and generate a new password file before restarting.
Database ID for database TSH2 changed to 1317278975.
All previous backups and archived redo logs for this database are unusable.
Shut down database and open with RESETLOGS option.
Succesfully changed database name and ID.
DBNEWID - Completed succesfully.
- STEP 4: Shutdown the database:
SHUTDOWN IMMEDIATE
- STEP 5: Modify the DB_NAME parameter in the
initialization parameter file. The startup will result in an error
but proceed anyway.
STARTUP MOUNT
ALTER SYSTEM SET DB_NAME=TSH2 SCOPE=SPFILE;
SHUTDOWN IMMEDIATE
- STEP 6: Create a new password file:
orapwd file=c:\oracle\920\database\pwdTSH2.ora password=password entries=10
- STEP 7: Rename the SPFILE to match the new DBNAME.
- STEP 8: If you are using Windows you must recreate the
service so the correct name and parameter file are used:
oradim -delete -sid TSH1
oradim -new -sid TSH2 -intpwd password -startmode a -pfile c:\oracle\920\database\spfileTSH2.ora
If you are using UNIX/Linux simply reset the ORACLE_SID environment
variable:
ORACLE_SID=TSH2; export ORACLE_SID
- STEP 9: Alter the listener.ora and tnsnames.ora setting
to match the new database name and restart the listener:
lsnrctl reload
- STEP 10: Open the database with RESETLOGS:
STARTUP MOUNT
ALTER DATABASE OPEN RESETLOGS;
- STEP 11: Backup the database.
For related notes, see:
