title: generating product 'suggestions' for users based on relative information from other users
body: <p>I have a database with three tables set up like this:</p>
  
  <p><em>Users</em>: username, user_id<br />
  <em>Products</em>: product_name, product_id<br />
  <em>User_Products</em>: product_id, user_id, relation_level</p>
  
  <p>These are all pretty straight forward, when a user clicks to 'like' a product, it asks how much they like it (rated 1-5) and stores that information in the User_Products table, storing the product_id from the Products table, user_id from the Users table and relation_level based on how much they like the product.</p>
  
  <p>What I want to do is generate suggestions for products the user might like, based on products the user likes and how much they like the products, getting users who like similar products and finding products the user doesn't already know about, based on the number of people who like them and the level they like them.</p>
  
  <p>Does anyone have any ideas how I can achieve this?</p>