PHP Help

Hey, Im making a site to where I can fill out a form and it adds updates to the main page, but I only want the site to display 5 updates on it, now I know how to make it only show 5 updates, but then that means when a new update is posted to the site, it just stores the old updates in the database and over time this can make the database quite large, How would I make it delete the oldest update and just add the newest update to the top of the list ? So this way I only have 5 updates stored in the database at all times. Thanks ConbuD --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.744 / Virus Database: 496 - Release Date: 8/24/2004