This may be a little different than most people do. I'm trying to show certain posts that are determined by 4 different "categories." I have a large database table full of "products" (I'm using the WP Products plugin, but I'm willing to change plugins). When a person comes to the site, they'll have 4 drop down menus to chose a specific category in each menu, and then query the results determined by those 4 categories.
I've been looking into
$wpdb to implement this. What is the best route to take in this situation?