Re: Oracle 8 and changing DB id's

From: Your Name <PatronID_at_ggr.co.uk>
Date: 29 Jun 1999 15:36:16 GMT
Message-ID: <01bec244$9be01070$aee5729f@ukd18084>

How about this. You'll find more on the oracle metalink. I've used this method before and it works fine.

 Document ID:        106373.655
Title:              Changing dbname or ORACLE_SID 
Creation Date:      07 September 1994

Last Revision Date: 07 September 1994 Revision Number: 0
Product: RDBMS
Product Version: 7
Platform: UNIX
Information Type: ADVISORY

Impact:             MEDIUM 
Abstract:           This bulletin describes how to change the dbname for a 
                    database, or the ORACLE_SID for an instance, without
                    having to recreate the database.
Keywords:           SID;DBNAME;CHANGING;ORACLE_SID;INSTANCE;CONTROLFILE 
-----------------------------------------------------------------------

Modifying a database to run under a new ORACLE_SID

Shutdown instance
Backup all control, redo and data files.
Go thru the .profile, .cshrc, .login, oratab, tnsnames.ora(for net v2),

and redefine the environment variable ORACLE_SID to a new value. ie search thru disks and do a grep ORACLE_SID * 4. cd $ORACLE_HOME/dbs and rename the following files:

o init<sid>.ora (or use pfile to point to the init file.) o control file(s) This is optional if you don't rename any of the

           controlfiles, and the control_files parameter is
           used.  control_files would be set in the initSID.ora
           file or in a file it references with the ifile
           parameter.  Make sure control_files doesn't point to
           any old file names, if you renamed them.
    o   crdb<sid>.sql & crdb2<sid>.sql       This is optional.  These are 
        only used at database creation.
5.  cd $ORACLE_HOME/rdbms/admin      and rename the file:  
    o   startup<sid>.sql      This is optional.

(On some platforms, this file may be in $ORACLE_HOME/rdbms/install.) Make sure the contents of this file do not reference old initSID.ora files that have been renamed. This file simplifies the process to "startup exclusive" your database.
6. To rename the database files and redo log files, you would follow the

instructions in the bulletin: 98863.723. 7. Change the ORACLE_SID environment variable to the new value. 8. start up database and verify it works. Once you have done this, shutdown

the database and take a final backup of all control, redo and data files.
9. When the instance is started, the control file gets updated with the

current ORACLE_SID.

Changing the dbname for a database

sqldba
connect internal
alter database backup controlfile to trace; This will write in a trace file, the CREATE CONTROLFILE command that would recreate the controlfile as it currently exists.
Exit and go to the directory where your trace files are located. They are usually in the $ORACLE_HOME/rdbms/log directory. If user_dump_dest is set in the initSID.ora, then go to the directory

     listed in the user_dump_dest variable. 
     The trace file will have the form "ora_NNNN.trc with NNNN being a

number.
5. Get the CREATE CONTROLFILE command from the trace file and put it in a

new file called something like ccf.sql. 6. Edit the ccf.sql file and modify the CREATE CONTROLFILE command.

Just change the word "REUSE" to "SET",and "NORESETLOGS" to "RESETLOGS",

     and modify the dbname.
     Old line:
         CREATE CONTROLFILE REUSE DATABASE "olddbname" NORESETLOGS ...
     New line: 
         CREATE CONTROLFILE set DATABASE "newdbname"  RESETLOGS ...
     Then save the ccf.sql file.

7. Rename the old control files for backup purposes and so they are not in

the way of creating the new ones.

 8.  Edit initSID.ora so that db_name="newdbname". 
 9.  sqldba 
10.  connect internal 
11.  startup nomount 
12.  @ccf 
13.  alter database open; 
14.  Make sure the database is working.  Shutdown and backup the database.

References

ORACLE7 SERVER, SQL Language Reference Manual

                                         Oracle Worldwide Customer Support

Glen Upreti <Glen.Upreti_at_NOSPAMnau.edu> wrote in article <3778D0E1.28F73209_at_nau.edu>...
> I had posted this a while back and just wanted to see if anyone has had
> the same problem.
>
> I have multiple database instances which I copy/clone into other
> database instances on the same machine. I basically copy the datafiles
> from one database and then run a create controlfile script which I
> extract from the source database. Although I would prefer doing it a
> cleaner way (export/import) the time it takes (5-6 hours) for that vs.
> the cloning method (10-20min) does not make it feasible.
>
> The problem is that because I am using a straight datafile copy the
> clone is really a clone of the original, and in Oracle 8 the dbid is not
> reset which means I can't use rman because rman cannot handle having
> multiple database instances with the same dbid.
>
> Is there any way to manually change the dbid? Is that OK or will oracle
> chase me down and beat me in the streets as a example of what not to do?
>
> Any help with this is greatly appreciated,
> Glen Upreti
>
>
> --
> |-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-|
> Glen Upreti
> Senior Oracle DBA
> Northern Arizona University
> Phone (520)523-8393 Fax(520)523-7407
> Glen.Upreti_at_nau.edu
Received on Tue Jun 29 1999 - 10:36:16 CDT