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A cold backup has the virtue of having the least number of steps in the restore process, which usually means the least chance of error, and it is faster than a hot backup.
A logical backup using the Oracle Export utility creates a file that has the information to re-create data structures and the data contained in the database. This information can be stored on a disk device or tape media. A logical backup takes longer than a physical backup and may require additional work in preparing the database for recovery. There are three Export modes:
You can control the Export utility using a parameter file to perform custom backups of data on the database. You can perform an export at three levels of data collection: incremental, cumulative, and complete. An incremental export backs up only data that has changed since the last incremental export. A cumulative export exports data only from tables that have changed since the last cumulative export; this export is used to condense the incremental exports. A complete export exports all data contained in a database. You should execute a complete export on a limited basis, due to the large volume of data collected.
Exports can be very flexible, but a regular schedule is important. It is a good idea to do a complete export on the first day of the month, an incremental export every day, and a cumulative report every weekend.l