This module introduced you to various methods for performing ARCHIVELOG database recovery. You learned that the recovery method you use depends on the state of the database.
You also leaned how to perform ARCHIVELOG database recovery using different methods.
Having completed this module, you should be able to:
- Describe the implications of instance failure with an ARCHIVELOG database
- Describe the different methods of recovery
- Describe a complete recovery operation
- Recover a closed database
- Recover an open database, initially open
- Recover an open database, initially closed
This module introduced you to the following terms:
- Instance failure: Instance failure means an abrupt end to an Oracle instance either due to a hardware or software problem.
The system global area and background processes cease to function. Therefore, any data in the buffer that had not already been written to a datafile at the time of the instance failure will be lost.
On the other hand, complete recovery recovers the damaged datafiles as well as all data that had been committed prior to the moment of instance failure.
- Complete recovery: Complete Oracle recovery, also known as complete media recovery, is applied to a database running in ARCHIVELOG mode. Complete recovery with archiving allows you to recover your database up to the time just
prior to the occurrence of media failure.
- System global area: The Oracle database employs several memory structures that are contained with the System Global Area (SGA).
The System Global Area contains three main in-memory structures. These memory structures may be tuned or modified by the DBA to improve performance. These memory structures include Shared Pool, Database Buffer Cache, and Redo Log Buffer.
In the next module, you learn how to perform incomplete Oracle recovery with archiving.