Available backup options in an Oracle Database

Backup and recovery is one of the most significant aspects of a DBA’s job. Usually one would schedule a hierarchy of daily, weekly and monthly backups, however consult with your users before deciding on a backup schedule.

An Oracle Database has following backing-up options. There are

1. Export/Import – Exports are “logical” database backups in that they extract logical definitions and data from the database to a file. 
2. Cold or Off-line Backups – Shut the database down and backup up ALL data, log, and control files.
3. Hot or On-line Backups – If the database is available and in ARCHIVELOG mode, set the tables spaces into backup mode and backup their files. Also remember to backup the control files and archived redo log files.
4. RMAN Backups – While the database is off-line or on-line, use the “rman” utility to backup the database.

Note that to use more than one of these methods to backup your database. For example, if you choose to do on-line database backups; also cover yourself by doing database exports. Also test ALL backup and recovery scenarios carefully. It is better to be safe than sorry.

Regardless of your strategy, also remember to backup all required software libraries, parameter files, password files, etc. If you database is in ARCHIVELOG mode, you also need to backup archived log files.

Original Source: http://www.orafaq.com/wiki/Oracle_database_Backup_and_Recovery_FAQ