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Lesson 8 The recovery catalog
Objective Discuss the role of the recovery catalog.

Recovery Catalog Role

Discuss the role of the recovery catalog.
From earlier lessons, you should now have an understanding of the recovery catalog. This lesson will further discuss the role of the recovery catalog.

The recovery catalog

The recovery catalog is an optional Oracle database and is treated like any other Oracle database, so you must include it in your backup plans. The recovery catalog is a set of tables stored in a special schema and maintained by Recovery Manager. These tables contain information about any backup, restore, or recovery operations. The recovery catalog stores the following information:
  1. Data file and archive log backup sets and the individual backup pieces
  2. Image copy information
  3. Archive redo logs and copy information
  4. Stored scripts
  5. Production database registration information
  6. Control file information, especially physical schema information

Why use a recovery catalog?

There are several reasons to use a recovery catalog. The primary reason is the ability to have Recovery Manager maintain information about your backups and also know which backup sets to restore in the event of a failure. Also, Oracle recommends that you use a recovery catalog.
Other important reasons include
  1. corruption detection,
  2. stored scripts for common activities,
  3. tablespace point-in-time recovery, and
  4. cumulative or noncumulative incremental backups.

Why not to use a recovery catalog?

The primary reason not to use a recovery catalog is that it may be unnecessary overhead or impractical. For instance, you would not use a recovery catalog for the databases on a laptop, which typically has a much less reliable disk system. If your disk dies, everything dies. Of course, you may not want or need store scripts or tablespace point-in-time recovery.
There are a number of other factors to consider with regard to your recovery catalog. Though these may seem obvious, it does not hurt to reinforce what you already know.
Review the Oracle backup and recovery documentation that provides some basic sizing information for your recovery catalog.
In the next lesson, you will learn how to create a recovery catalog.