title: What would it mean If I change the identifying relationship from this part of a database design to a non-identifying relationship?
body: <p>I have a question regarding this database design. I am a bit unsure of the difference between identifying and non-identifying relationships in a database leading me to some puzzles in my head. </p>
  
  <p>I have this database design: <em>(kind of like a movie rental stores. "friend" are those who borrow the movie. "studio" is the production studios that collaborated in making the movie.)</em></p>
  
  <p><img src="https://i.stack.imgur.com/VxqRn.png" alt="Sample.png"></p>
  
  <p>I somewhat understand how it works. However, I was wondering what if I create a <strong>loan_id</strong> in the loan table, and use <strong>movie_id</strong> and <strong>friend_id</strong> as normal foreign keys? </p>
  
  <p>Some of my questions are:
  What are the advantages or disadvantages of the later approach? 
  A situation where the initial or later model is better?
  Does the initial model enable a friend to borrow a movie more than once?</p>
  
  <p>Any thorough explanation would be much appreciated.</p>