Let’s learn how how to schedule automatic backups.
To schedule a backup, go to the Backup tab under Manage on your WordPress Dashboard and scroll down until you see the Scheduled Backup option. The plugin allows you to schedule a database dump hourly once, daily once, daily twice, or weekly once. Select the frequency that fits your needs (Once Daily is my personal choice) and enter your email address. As per your selection of the frequency, you'll receive a database backup by email.
WP Database Backup is a PHP script that executes lots of SQL commands using PHP functions to create a database backup.
If you're looking for an even more powerful plugin, you should definitely try the WP-DBManager (http://lesterchan.net/wordpress/readme/wp-dbmanager.html).
This plugin allows you to create backups of your WordPress database just as WP Database Backup does, but you can also repair and optimize your database, and even, run SQL commands...