CodeGuard backup uses the industry standard mysqldump tool to back up MySQL databases, and does so in such a way that enables the live database to continue to function while also ensuring integrity and consistency of the database backup.
The mysqldump is executed using the 'single-transaction' option. This ensures consistent state of the backup without locking the database. Single-transaction, along with the options 'quick' and 'skip-extended-insert', allow backup of the live database at a point in time without blocking any applications.
CodeGuard backups using mysqldump also ensure low server load, ensuring that the website will continue to function normally while the backup runs in the background. CodeGuard has published results of our msyqldump database backup load testing, which can be found on our blog at http://blog.codeguard.com/database-backup-load-analysis/
More information about how mysqldump works is available at http://dev.mysql.com/doc/refman/5.1/en/mysqldump.html