What are Differential and Incremental Backup Types?
Both Differential and Incremental Backup Types will only backup files that have changed since the last backup (files whose Archive bit is set to True – see the next question). Incremental backups will clear the archive bit of all the files they backup. Differential backups will not clear the archive bit of the files they backup. Lets assume we start with a normal backup that clears the archive bit of all our data files. If we perform a series of Incremental backups, only those files that have changed since the last incremental backup will be included in each backup. To restore from a series of Incremental backups, we need to restore from the Normal backup and each Incremental backup in the order they were created, but no unchanged files will ever be included in a backup. If we perform a series of Differential backups, all the files that have changed since the original Normal backup will be included. Once a file has changed, it will be included in each Differential backup. To restore, w
