Lost Oracle administrator username and password that run on Unix system

[T G Manikandan]

Hello,
It is good that you are backing up the database.
If it is a database of importance you/it cannot be backed up with the comments/commands,I am writing.
If the database is a normal one,then

You can do a cold backup of the database.
Cold back up is to shutdown the database and continue the back up.
ORACLE_SID='instance_name'
$svrmgrl
SVRMGR>connect internal
Before you shut down the database
query for the datafiles,logfiles,controlfile
of the database that requires backup.
SVRMGR>select name from v$datafile;
SVRMGR>select * from v$controlfile;
SVRMGR>select * from v$logfile;
The above queries will return the OS path where the files reside.Then,
SVRMGR>shutdown immediate;
Now use your OS 'cp' command to copy the files
to the other part of the disk or backup to the tape.
The above method applies if your database is running on noarhivelog.
SVRMGR>select log_mode from v$database;
If your database is running on archivelog,
then
you should also backup the archived-log files.

You can also use the export utility to backup the database

$$ORACLE_HOME/bin/exp "username/passwd"@"instance_name full=y file="path of the dump file".

Here the above syntax
full--->full backup
file--->path of the dump file.
This will export all the objects into a file which you can import it on another database with appropriate user.

So when you export check the tablespace_names,datafile-names,users on the database.
If problem exists then you can recreate the database if the same-tablespace,datafile and user names and import the dump file to restore the objects.

My post will not provide you proper understanding.Please refer to
backup and administrator guide.
The size of the file is 5MB.please give your mail address,I will mail it.
Also check your oracle cd for the documentation.

Your 20 points already given are enough for my posts


Thanks

[Jacky Wong_1]

I got 2 problem now. Firstly, When I input the below command in svrmgrl prompt

svrmgrl>alter user system identified by 1234

Then press "enter", it only change to next new line and not run the command. How can I run this command. I want to change the system password to 1234.

Secondly, when I use cold backup in noarhivelog mode. Can I export the datafile only and import it in the new database? Cause I will install a new one and only need the old database data. Or I must export the old database datafile, logfile, controlfile and import all to new one?

[Sanjay_6]

Hi Jacky,

I think you should use ";" at the end of the command in "svrmgrl".

Hope this helps.

Regds

[Jacky Wong_1]

But when I typing "alter user system identified 1234;"

The output is "ORA-00988:missing or invalid password(s)"

Why I cannot change the system account password?

Please help!

[T G Manikandan]

Hello,
Just change your password with
the password starting with a alphabet

ex:a1234
Then,
If your database is running on the noarchivelog mode then you can take a cold backup after shutting down the database.

cp the datafiles,logfiles,controlfile to different locations of your database.
So when you need to recreate database with the copied datafiles then you can point the database to look at these files where you copied.(may be on a second machine)
you can do this easily using the RMAN where you can duplicate your existing database to another machine.
Just check your manual.

Thanks

[Lim Win Hwang]

If you would like to use "1234" as your password, then you can type this:
alter user system identified "1234";

Regards,
win