title: Create Rails query using LIKE that searches over association tables
body: <p>I would like to write a Rails query using Postgresql 'LIKE'. I want to be able to search a column on the current table as well as an association table.</p>
  
  <p>I can search the current table like this:
  <code>User.where("description LIKE ?", "%happy%")</code></p>
  
  <p>I can search associations like this: 
  <code>User.joins(:products).where("products.description LIKE ?", "%happy%")</code></p>
  
  <p>How do I combine these 2 queries into one? I want to return all users whose description contains "happy" and/or has a product whose description contains "happy".</p>