Database will not up

[oracle8]

When i startup my database it will not start coz an error will appear 'Ora:01157 : can not identify datafile 6 - file not found'. When i checked the file i found out that the filesize of datafile 6 is zero. Lately, our server was infected by a virus (nimda) and i suspect our datafile 6 is zero coz it was heat by the virus. I'm using oracle 8.05 on NT box.

There are few things that i want to do in order to solve this problem and i need your wisdom if i am doing the right thing 'coz i'm new to oracle.

1. I have a cold backup of my datafiles a week ago. Will it be okay to restore the datafile 6 from tape to disk ?
2. Do i need to import the database ?

Pls. i need your advice. thanks

Rommel

 

[KenCunningham]

Unfortunately, I don't think restoring just datafile6 will solve your problem since the control files etc will be out of whack with the older version. There may be a way around this and the gurus here may well be able to explain what to do. However, my own opinion is that a full restore from your cold backup may be required to ensure consistency accross your database. No import should be required if this is the case. I'd hold fire a while, however, as others may well have better and more informed advice than this. Good luck.

 

[richardszm]

What KenCunningham is absolut right.
You cannot only bring back your datafile 6 from tape .
you must restore the whole database tablespaces and logfiles.
You lost your data since your last backup.
If you run in archive mode than you can bring your database on the actually status again.
But you must take the completed backup.

Select value from V$PARAMETER where name ='log_archive_start';
return 'TRUE' when running in archive_mode.
Richard

 

[DaPi]

If you run in ARCHIVELOG mode then you should be able to get your db back with no data loss (no such luck if you don't).

HOWEVER DON'T DO A FULL RESTORE (Though I guess I'm too late). The Oracle doc specifically says ONLY restore the damaged data file(s). I'm sure you will not succed if you restore all and overwrite the current log and control files.
(BTW, this is a strong argument for making a cold backup of the corrupted situation before attempting a recovery! Errare humanum est!)

Ken said: "control files etc will be out of whack with the older version". YES! this is exactly what Oracle needs so that it can determine what needs to be done to fix the restored file. DaPi - no silver bullet

 

[DaPi]

To be complete - once you have restored the datafile and all the archivelogs are in the right place, you need to MOUNT the data base and issue sometging like ALTER DATABASE RECOVER AUTOMATIC. Then shutdown & startup. If all the logs are in place, it works like a dream! DaPi - no silver bullet