An Oracle instance is a collection of allocated memory (System Global Area) and running process (SMON, PMON, LGWR, DBWR) on the server. Once the instance starts, Oracle allocates the instance with a particular database. This process is known as mounting of the database, which enables the DBA (Database Administrator) to access the database records. Oracle Instance failure is an issue that occurs when the database gets corrupted or damaged due to hardware or logical crash. In such cases, the Oracle database records become inaccessible. To surmount the above corruption situation and to access the database records, a DBA can restore the data from an updated backup. However, if in case, DBA has not performed complete backup, then s/he needs to repair the corrupt Oracle database. To systematically do so, a DBA needs an effective third-party Oracle Database Recovery application.

Consider a practical case, where you – using your administrative privileges – attempt to mount your Oracle database, by starting the instance using below command:

oradim -new -sid %ORACLE_SID% -pfile c:\path\to\your\init.ora

However, instead of instance starting up, an error message pops stating that it could not be started. As the database remains unmountable, the records stored in the database also remain inaccessible.

Cause:

The above situation occurs under following circumstances:

You do not have sufficient privileges to start the instance.
The parameter file could not be opened.
Your database is corrupted due to operating system crash.

Resolution:

Below guideline enable you to start the instance and access the database records:
Ensure that you have sufficient privileges and are a part of DBA group.
Ensure that the parameter file is at its default location.
In case of oracle database corruption, if no backup is available, you will need to use an advanced Oracle Database Recovery application.

An DBF Recovery tool incorporates powerful scanning algorithms to repair corrupt database and bring it to a usable state. The repaired database can be saved at the destination provided by DBA. The database repair tool allows both home users and DBAs to perform database repair.

Oracle Recovery is a reliable Oracle Recovery software that repairs damaged databases post any corruption scenario. The read only utility safely recovers all Oracle database objects, like tables, synonyms, views, table spaces, indexes, and sequences. Supported by Oracle 9i, the tool is designed for Windows XP and 2003 operating systems.