Repeated Parenting Queries

Folks, For a site of mine, I've made an ODP-like <http://dmoz.org> interface, that is actually pretty much identical to the ODP. Once I'm done, I'll open source it, I guess. The problem that I'm having is determining the parents of each level of abstraction. To consider an example from the ODP, we have this category: Top: Sports: Olympics: Summer Games: Sydney 2000: News and Media If somebody goes to the "News and Media" page, there are 5 lookups to the category-parenting system, to determine each parent until hitting category 1, "Top," at which point that it stops. I'm currently looping a MySQL query in order to gather this data (query the DB, add the result to an array, if category_id != 1, loop), but it seems grossly inefficient. I've set up caching, so it only checks each category once every 12 hours, but that's hardly a fix for poor code on my part. My question is this: Is there a single query, or a tighter loop, that I could use to make this a little cleaner? This current setup really sucks, and it's the only reason that I haven't launched the site yet. I'm worried somebody may find out about my lame parenting query. :) Any suggestions? TIA, Waldo