Database recovery

[ramuganapathi]

There are 100 datafiles, numbered from 1 to 100. File number 10 is deleted and it has 500 MB of data. The database is working in No- Archive log mode. How can the database be recovered?

[vinodkmg]

Hi Ramu,

Is your database production or a test DB.

If you database is in no-archive mode,there is no way you can recover.Only option is restore from the previous day's backup.

[natram]

If you don't have your db on archive log mode, your only option is to restore from your latest cold backup.

[ramuganapathi]

Thanks for your answers.

As I am new to DBA, currently working in a test database.

In fact the same answer I had in my mind. I want to make sure that is there is anyother way to recover the datafile.
If we replace the corrupt file with the backup file dont you think the control file should also be replaced.
This may lead to loss of data.

Please correct me if am wrong

[vinodkmg]

You need to restore the entire database from consistant backup & open the database.if you restore only the lost file and the control file you cant bring your database up because the SCN in control file wont match with the datafile headers of the other files.

Solution is to restore the entire database from the consistant backup.

Regards,
Vinod

[bang_dba]

Hi,
Use offline drop option for the datafile 10 and open the database.
This ensures that u can reatain rest 99 datafiles with the latest data.
But there is no other way to recover the 10th datafile with latest changes.

[pando]

Originally posted by bang_dba
Hi,
Use offline drop option for the datafile 10 and open the database.
This ensures that u can reatain rest 99 datafiles with the latest data.
But there is no other way to recover the 10th datafile containing the latest changes.

hope you understand that you need to drop the tablespace after offline dropping a datafile

[bazza]

If you have the resources, you could open the database as suggested with the 99 datafiles, restore your last consistent backup somewhere else and export/import your missing data back into the original database...whether that is practical or not depends on your situation.

Bazza