Microsoft® SQL Server 2012 Unleashed

Full Database Backups with Transaction Log Backups

Compared to making a full database backup only, a more comprehensive approach to database backups includes the use of transaction log backups to augment the recoverability of full database backups. Transaction log backups that are taken periodically capture incremental database activity that can be applied to a full database backup during database restore.

You need to measure the frequency of the transaction log backup against the tolerance for data loss. For example, if the requirement is to prevent no more than one hour’s worth of work, the transaction log backups should be taken hourly. If the media on which the backup is stored is accessible, you should lose no more than one hour’s worth ...