DevShed finishes off their series on database security in PHP applications with this look at protecting your application and data from the threat of SQL injections.

In this article we will continue to explore various attacks that can be made on a database and how to prevent these attacks. We will also build the last page of our site.

Their example script is a login for a secured area of the site and contains a possible place for an injection - non-validated user input. With something as simple as making the username a single quote, an attacker could find out more about your database structure and use that to get further into your systems. To avoid it, they recommend validating with the mysql_real_escape_string function as a first line of defense.