Caching Information

[eluser]newsmuncher[/eluser]
Query cache is turned on and the directiory is set correctly, I haven't altered the query or page in any way, but from phpMyAdmin if i change the username related to the id i want, the cache recognizes this and changes it. I know the query is being cached because if i manually delete the cached query's it generates them again and places them in the cached folder.

I can't understand why, only explanation i suppose would be that its running the query and caching it on every page load, which is pointless....