Differentiate Hot and Cold Backup.
Cold Backup– We can take the Backup while DB(eg. Oracle ) is down.
Hot Backup-We can take the Backup while DB(eg. Oracle) is running.
Cold backup is a physical backup. During a cold backup the database is closed and not available to users. All files of the database are copied (image copy). The datafiles do not change during the copy so the database is in sync upon restore.
Used when:Service level allows for some down time for backup
Hot backup is a physical backup. In a hot backup the database remains open and available to users. All files of the database are copied (image copy). There may be changes to the database as the copy is made and so all log files of changes being made during the backup must be saved too. Upon a restore, the changes in the log files are reapplied to bring the database in sync. Used when:A full backup of a database is needed Service level allows no down time for the backup.
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