mySQLl on Apache web server

Hi all, I have an apache web server running on SuSE 7.3 with PHP4. I would like to install mySQL on it now. I used Marc Heuse document on Securing a Web Server which I found very helpful, but he did not mention much about the database stuff. What security risks am I allowing by putting mySQL on this Web Server? What extra steps will I need to take? Is there a document somewhere that outlines the steps to securing mySQL on SuSE? Thanks, Robert