title: Is an advanced (multiple) join possible with dplyr?
body: <p>is it possible to do a join as the example ERD with dplyr?</p>
  
  <p>see advanced join ERD example:</p>
  
  <p><a href="https://i.stack.imgur.com/PgDeu.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/PgDeu.png" alt="ERD example"></a></p>