I've been wondering about how my site is setup lately. I haven't found many other sites that use a site structure like mine, so I'm kind of wondering if there are any disadvantages to the way my site is setup.

When you browse my site at http://www.supercarcentral.com, a visitor uses the same page the entire time. This page is called index.php and depending on variables passed through the url(like this: http://www.supercarcentral.com/index...in&carselect=z) and through forms, the page uses the require() or include() functions to include the correct file for the page based on the variable "action" in the url. Also, page names are determined by the action variable. A connection to the mySQL database is made only once, and it's made on index.php, so that the included connections don't have to have mysql_connect in them.

There are many advantages to this structure, one of them being that I only have to update one file when I want to change the entire design for the site. I also don't have as many big php files on the server.

I'm wondering if you guys know of any disadvantages of having my site setup like this.