Backup Tools

Oracle Database provides the following tools to manage backup and recovery of Oracle Databases. Each tool gives you a choice of several basic methods for making backups. The methods include:

  • Oracle Recovery Manager (RMAN)

    RMAN reduces the administration work associated with your backup strategy by maintaining an extensive record of metadata about all backups and needed recovery-related files. In restore and recovery operations, RMAN uses this information to eliminate the need for the user to identify needed files. RMAN is efficient, supporting file multiplexing and parallel streaming, and verifies blocks for physical and (optionally) logical corruptions, on backup and restore.

    Backup activity reports can be generated using V$BACKUP views.

  • Oracle Data Pump

    Oracle Data Pump provides high speed, parallel, bulk data and metadata movement of Oracle Database contents. This utility makes logical backups by writing data from Oracle Database to operating system files. This data can later be imported into Oracle Database.

  • User-Managed Backups

    The database is backed up manually by executing commands specific to your operating system.

Oracle Recovery Manager (RMAN)

Oracle Recovery Manager (RMAN), a command-line is the Oracle-preferred method for efficiently backing up and recovering Oracle Database. RMAN is designed to work intimately with the server, providing block-level corruption detection during backup and recovery. RMAN optimizes performance and space consumption during backup with file multiplexing and backup set compression, and integrates with leading tape and storage media products with the supplied Media Management Library (MML) API.

RMAN takes care of all underlying database procedures before and after backup or recovery, freeing dependency on operating system and SQL*Plus scripts. It provides a common interface for backup tasks across different host operating systems, and offers features not available through user-managed methods, such as data file and tablespace-level backup and recovery, parallelization of backup and recovery data streams, incremental backups, automatic backup of the control file on database structural changes, backup retention policy, and detailed history of all backups.

See Also:

Oracle Database Backup and Recovery User's Guide for more information about RMAN

Oracle Data Pump

Physical backups can be supplemented by using the Oracle Data Pump (export/import) utilities to make logical backups of data. Logical backups store information about the schema objects created for a database. Oracle Data Pump loads data and metadata into a set of operating system files that can be imported on the same system or moved to another system and imported there.

The dump file set is made up of one or more disk files that contain table data, database object metadata, and control information. The files are written in a binary format. During an import operation, the Data Pump Import utility uses these files to locate each database object in the dump file set.

User-Managed Backups

If you do not want to use Recovery Manager, you can use operating system commands, such as the UNIX dd or tar commands, to make backups. To create a user-managed online backup, the database must manually be placed into hot backup mode. Hot backup mode causes additional write operations to the online log files, increasing their size.

Backup operations can also be automated by writing scripts. You can make a backup of the entire database immediately, or back up individual tablespaces, data files, control files, or archived logs. An entire database backup can be supplemented with backups of individual tablespaces, data files, control files, and archived logs.

Operating system commands or third-party backup software can perform database backups. Conversely, the third-party software must be used to restore the backups of the database.