multi dynamic checks

Please forward this to the correct address, I could not find a better one. I have searched the net and cannot find successful assistance. I have a list of articles that have several categories each. I have a list of affiliates that also have several categories each. I have a list of categories to apply to both. I have five tables to ease data management (articles, affiliates, categories, article / category junction, and affiliate / category junction) All three lists have to remain dynamic. Using only php, how can I display the affiliates who's category corresponds to the article. I've rewritten queries, attempted foreach loops, attempted switch / case, attempted dynamically set arrays (to which NO ONE can do). I'm lost. Please help. Paul info@cobblestoneplaza.com