title: Customers who bought this also bought this... Help
body: <p>Hi trying to figure out this, have looked in many places but because of my table structure I'm struggling. Here is my table structure:</p>
  
  <p><strong>users</strong> - id, login (pk)</p>
  
  <p><strong>lessons</strong> - id (pk), name</p>
  
  <p><strong>users_to_lessons</strong> - users_LOGIN (fk), lessons_ID (fk)</p>
  
  <p>How can I implement a "customers who bought this also bought this..." feature?</p>