Database Mirroring is a backup model which is preferred for 24 hours operational databases. A copy of the perational database is kept on a second (Mirror) server and it is updated periodically by sending a log file from the main to the mirroring database. The log file is generated from a backup procedure or programmatically. In case of anaccident of the operational database, the mirror database can be used to get things back, quickly and with no data loss.