22 DBNEWID Utility
DBNEWID
is a database utility that can change the internal
database identifier (DBID
) and the database name (DBNAME
)
for an operational database.
- What Is the DBNEWID Utility?
TheDBNEWID
utility enables you to change only theDBID
,DBNAME
, or both theDBID
andDBNAME
of a database. - Ramifications of Changing the DBID and DBNAME
Before you change theDBID
andDBNAME
of a database with the DBNEWID utility, review these guidelines. - Considerations for Global Database Names
If you are dealing with a database in a distributed database system, then each database should have a unique global database name. - Changing Both CDB and PDB DBIDs Using DBNEWID
The DBNEWID parameterPDB
enables you to change theDBID
on pluggable databases (PDBs). - Changing the DBID and DBNAME of a Database
To change eitherDBID
orDBNAME
, or both theDBID
andDBNAME
of your database, select the DBNEWID procedure that you need. - DBNEWID Syntax
To change only theDBID
,DBNAME
, or both theDBID
andDBNAME
of a database, useDBNEWID
.
Parent topic: Other Utilities
22.1 What Is the DBNEWID Utility?
The DBNEWID
utility enables you to change only the
DBID
, DBNAME
, or both the DBID
and
DBNAME
of a database.
Before the introduction of the DBNEWID utility, you could manually create a
copy of a database and give it a new database name (DBNAME
) by
recreating the control file. However, you could not give the database a new identifier
(DBID
). The DBID
is an internal, unique identifier
for a database. Because Recovery Manager (RMAN) distinguishes databases by
DBID
, you could not register a seed database and a manually copied
database together in the same RMAN repository. The DBNEWID utility solves this problem
by enabling you to change any of the following:
- Only the
DBID
of a database - Only the
DBNAME
of a database - Both the
DBNAME
andDBID
of a database
Parent topic: DBNEWID Utility
22.2 Ramifications of Changing the DBID and DBNAME
Before you change the DBID
and DBNAME
of a
database with the DBNEWID utility, review these guidelines.
When you change the DBID
, you should make a backup of the whole database
immediately.
Changing the DBID
of a database is a serious procedure. When the
DBID
of a database is changed, all previous backups and archived
logs of the database become unusable. Changing the DBID
is similar to
creating a database, except that the data is already in the data files. After you change
the DBID
, backups and archive logs that were created before the
DBID
change can no longer be used, because they still have the
original DBID
, which does not match the current DBID
.
You must open the database with the RESETLOGS
option, which recreates
the online redo logs, and resets the redo log sequence to 1. Consequently,
When you change DBNAME
and do not change DBID
, you must
change the DBNAME
initialization parameter, and follow additional
guidelines.
Changing the DBNAME
without changing the DBID
does
not require you to open with the RESETLOGS
option, so database backups
and archived logs are not invalidated. However, changing the DBNAME
does have consequences. You must change the DB_NAME
initialization
parameter after a database name change to reflect the new name. Also, you may have to
recreate the Oracle password file. If you restore an old backup of the control file
(before the name change), then you should use the initialization parameter file and
password file from before the database name change.
Caution:
If you are using a capture process to capture changes to the database,
then do not change the DBID
or DBNAME
of a
database .
Parent topic: DBNEWID Utility
22.3 Considerations for Global Database Names
If you are dealing with a database in a distributed database system, then each database should have a unique global database name.
The DBNEWID utility does not change global database names.
You can only change a global database name with the SQL ALTER
DATABASE
statement, for which the syntax is as follows:
ALTER DATABASE RENAME GLOBAL_NAME TO newname.domain;
The global database name is made up of a database name and a domain, which are determined by the DB_NAME
and DB_DOMAIN
initialization parameters when the database is first created.
For example, suppose you use DBNEWID to change a database name to
sales
. To ensure that you also change the global database name to
sales
in the domain example.com
, you should use
ALTER DATABASE RENAME
as follows:
ALTER DATABASE RENAME GLOBAL_NAME TO sales.example.com
See Also:
Oracle Database Administrator’s Guide for more information about global database names
Parent topic: DBNEWID Utility
22.4 Changing Both CDB and PDB DBIDs Using DBNEWID
The DBNEWID parameter PDB
enables you to change the
DBID
on pluggable databases (PDBs).
By default, when you run the DBNEWID utility on a container database (CDB), the
utility only changes the DBID
of the CDB. The DBID
values for each of the pluggable databases (PDBs) plugged into the CDB remain the same.
In some cases, you can find that this default behavior causes problems with duplicate
DBID values for PDBs. For example, you can encounter this issue when a CDB is
cloned.
With Oracle Database 12c Release 2 (12.2) and later releases, you can use the
DBNEWID utility PDB parameter in multitenant databases to change the DBID values for
PDBs. You cannot specify a particular PDB; either all of them or none of them are
assigned new DBID
values.
The
PDB
parameter has the following format:
PDB=[ALL | NONE]
-
If you specify
ALL
, then in addition to theDBID
for the CDB changing, theDBID
values for all PDBs plugged into the CDB are also changed. -
Specifying
NONE
(the default) leaves the PDBDBID
s the same, even if the CDBDBID
is changed.
Oracle recommends that you use PDB=ALL
. For backward compatibility,
the default is PDB=NONE
.
Parent topic: DBNEWID Utility
22.5 Changing the DBID and DBNAME of a Database
To change either DBID
or DBNAME
, or both
the DBID
and DBNAME
of your database, select the DBNEWID
procedure that you need.
- Changing the DBID and Database Name
To change theDBID
of a database, or both theDBID
andDBNAME
of a database with DBNEWID, use this procedure. - Changing Only the Database ID
To change the database ID (DBID
) without changing the database name, use this DBNEWID procedure. - Changing Only the Database Name
To change the database name (DBNAME
) without changing theDBID
, use this DBNEWID procedure. - Troubleshooting DBNEWID
If you encounter an error when using DBNEWID to change a database ID, then refer to these troubleshooting hints.
Parent topic: DBNEWID Utility
22.5.1 Changing the DBID and Database Name
To change the DBID
of a database, or both the
DBID
and DBNAME
of a database with DBNEWID, use this
procedure.
DBID
of a
database. You also have the option to change the database name as well.
Parent topic: Changing the DBID and DBNAME of a Database
22.5.2 Changing Only the Database ID
To change the database ID (DBID
) without changing the
database name, use this DBNEWID procedure.
Follow the steps in Changing the DBID
and Database Name, but in Step 3 do not specify the optional database
name (DBNAME
). The following is an example of the type of output
that is generated when only the database ID is changed.
. . . Connected to database PROD (DBID=86997811) . . . Control Files in database: /oracle/TEST_DB/data/cf1.dbf /oracle/TEST_DB/data/cf2.dbf The following datafiles are offline clean: /oracle/TEST_DB/data/tbs_61.dbf (23) /oracle/TEST_DB/data/tbs_62.dbf (24) /oracle/TEST_DB/data/temp3.dbf (3) These files must be writable by this utility. The following datafiles are read-only: /oracle/TEST_DB/data/tbs_51.dbf (15) /oracle/TEST_DB/data/tbs_52.dbf (16) /oracle/TEST_DB/data/tbs_53.dbf (22) These files must be writable by this utility. Changing database ID from 86997811 to 4004383693 Control File /oracle/TEST_DB/data/cf1.dbf - modified Control File /oracle/TEST_DB/data/cf2.dbf - modified Datafile /oracle/TEST_DB/data/tbs_01.dbf - dbid changed Datafile /oracle/TEST_DB/data/tbs_ax1.dbf - dbid changed Datafile /oracle/TEST_DB/data/tbs_02.dbf - dbid changed Datafile /oracle/TEST_DB/data/tbs_11.dbf - dbid changed Datafile /oracle/TEST_DB/data/tbs_12.dbf - dbid changed Datafile /oracle/TEST_DB/data/temp1.dbf - dbid changed Control File /oracle/TEST_DB/data/cf1.dbf - dbid changed Control File /oracle/TEST_DB/data/cf2.dbf - dbid changed Instance shut down Database ID for database TEST_DB changed to 4004383693. All previous backups and archived redo logs for this database are unusable. Database has been shutdown, open database with RESETLOGS option. Succesfully changed database ID. DBNEWID - Completed succesfully.
Parent topic: Changing the DBID and DBNAME of a Database
22.5.3 Changing Only the Database Name
To change the database name (DBNAME
) without changing the
DBID
, use this DBNEWID procedure.
Complete the following steps:
Parent topic: Changing the DBID and DBNAME of a Database
22.5.4 Troubleshooting DBNEWID
If you encounter an error when using DBNEWID to change a database ID, then refer to these troubleshooting hints.
If the DBNEWID utility succeeds in its validation stage, but detects an error while performing the requested change, then the utility stops and leaves the database in the middle of the change. In this case, you cannot open the database until the DBNEWID operation is either completed, or it is reverted. DBNEWID displays messages indicating the status of the operation.
Before continuing or reverting, fix the underlying cause of the error. Sometimes the only solution is to restore the whole database from a recent backup and perform recovery to the point in time before DBNEWID was started. This scenario underscores the importance of having a recent backup available before you DBNEWID.
If you choose to continue with the change, then rerun your original command.
The DBNEWID utility resumes, and attempts to continue the change until all data files
and control files have the new value or values. At this point, the database is shut
down. You should mount it before opening it with the RESETLOGS
option.
If you choose to revert a DBNEWID operation, and if the reversion succeeds, then DBNEWID reverts all performed changes and leaves the database in a mounted state.
If DBNEWID is run against Oracle Database 10g Release 1 (10.1) or a later release Oracle Database, then a summary of the operation is written to the alert file.
Example 22-1 Alert Files for a Database Name and Database ID Change
Suppose you changed a database name and database ID. In the alert file, you see something similar to the following:
*** DBNEWID utility started *** DBID will be changed from 86997811 to new DBID of 1250452230 for database PROD DBNAME will be changed from PROD to new DBNAME of TEST_DB Starting datafile conversion Setting recovery target incarnation to 1 Datafile conversion complete Database name changed to TEST_DB. Modify parameter file and generate a new password file before restarting. Database ID for database TEST_DB changed to 1250452230. All previous backups and archived redo logs for this database are unusable. Database has been shutdown, open with RESETLOGS option. Successfully changed database name and ID. *** DBNEWID utility finished successfully ***
For a change of just the database name, the alert file might show something similar to the following:
*** DBNEWID utility started *** DBNAME will be changed from PROD to new DBNAME of TEST_DB Starting datafile conversion Datafile conversion complete Database name changed to TEST_DB. Modify parameter file and generate a new password file before restarting. Successfully changed database name. *** DBNEWID utility finished successfully *** In case of failure during DBNEWID the alert will also log the failure: *** DBNEWID utility started *** DBID will be changed from 86997811 to new DBID of 86966847 for database AV3 Change of database ID failed. Must finish change or REVERT changes before attempting any database operation. *** DBNEWID utility finished with errors ***
Parent topic: Changing the DBID and DBNAME of a Database
22.6 DBNEWID Syntax
To change only the DBID
, DBNAME
, or both
the DBID
and DBNAME
of a database, use
DBNEWID
.
The following diagrams show the syntax for the DBNEWID
utility.
- DBNEWID Parameters
Describes the parameters for DBNEWID. - Restrictions and Usage Notes
Describes restrictions for the DBNEWID utility. - Additional Restrictions for Releases Earlier Than Oracle Database 10g
Describes additional restrictions if the DBNEWID utility is run against an Oracle Database release earlier than 10.1.
Parent topic: DBNEWID Utility
22.6.1 DBNEWID Parameters
Describes the parameters for DBNEWID.
The following table describes the parameters in the DBNEWID syntax.
Table 22-1 Parameters for the DBNEWID Utility
Parameter | Description |
---|---|
|
Specifies the username and password used to connect to the database. The user must have the |
|
Specify |
|
Changes the database name of the database. You can change the DBID and the DBNAME of a database at the same time. To change only the DBNAME, also specify the |
|
Specify |
PDB |
Changes the DBID on either all or none of the pluggable databases (PDBs) in a multitenant container database (CDB). (By default, when you run the DBNEWID utility on a container database (CDB) it changes the DBID of only the CDB; the DBIDs of the pluggable databases (PDBs) comprising the CDB remain the same.) The PDB parameter is applicable only in a CDB environment.
|
|
Specifies that DBNEWID should write its messages to the specified file. By default the utility overwrites the previous log. If you specify a log file, then DBNEWID does not prompt for confirmation. |
|
Specify |
|
Specify |
Parent topic: DBNEWID Syntax
22.6.2 Restrictions and Usage Notes
Describes restrictions for the DBNEWID utility.
For example:
-
To change the DBID of a database, the database must be mounted and must have been shut down consistently before mounting. In the case of an Oracle Real Application Clusters database, the database must be mounted in
NOPARALLEL
mode. -
You must open the database with the
RESETLOGS
option after changing the DBID. However, you do not have to open with theRESETLOGS
option after changing only the database name. -
No other process should be running against the database when DBNEWID is executing. If another session shuts down and starts the database, then DBNEWID terminates unsuccessfully.
-
All online data files should be consistent without needing recovery.
-
Normal offline data files should be accessible and writable. If this is not the case, then you must drop these files before invoking the DBNEWID utility.
-
All read-only tablespaces must be accessible and made writable at the operating system level before invoking DBNEWID. If these tablespaces cannot be made writable (for example, they are on a CD-ROM), then you must unplug the tablespaces using the transportable tablespace feature and then plug them back in the database before invoking the DBNEWID utility.
-
The DBNEWID utility does not change global database names. See Considerations for Global Database Names.
Parent topic: DBNEWID Syntax
22.6.3 Additional Restrictions for Releases Earlier Than Oracle Database 10g
Describes additional restrictions if the DBNEWID utility is run against an Oracle Database release earlier than 10.1.
For example:
-
The
nid
executable file should be owned and run by the Oracle owner because it needs direct access to the data files and control files. If another user runs the utility, then set the user ID to the owner of the data files and control files. -
The DBNEWID utility must access the data files of the database directly through a local connection. Although DBNEWID can accept a net service name, it cannot change the DBID of a nonlocal database.
Parent topic: DBNEWID Syntax