05 February 2012
suppose u take full backup on 1st feb, 3rd feb nd 5th feb u take both incremnetal and diff backup
the backup on 3rd feb will be same in both diff and incremental
but the backup on 5th feb will be diff in following way incremental backup..only data changed between 3-5th will be backed up differential backup..all data changed between 1-5th will be backed up
so in case u need to restore data on 5th feb under incremental backup u'll need all 3 backups
under differential backup..only 1st ka full backup nd 5th ka diff backup is enuff!!