title: Firebase correct logic
body: <p>Wondering if I have the right mindset here... In firebase (with Vue) I have a userscollection:</p>
  
  <pre><code>users : {
      uid: "09A09IQMSLDK0912",
      name: "Gerard",
      email: "gerard@mail.com"
  }
  </code></pre>
  
  <p>If I want the user to add friends, should I add it to the userscollection?</p>
  
  <pre><code>users : {
      uid: "09A09IQMSLDK0912",
      name: "Gerard",
      email: "gerard@mail.com",
      friends: []
  }
  </code></pre>
  
  <p>... or should I start a new collection (e.g. friendscollection)?</p>
  
  <pre><code>friends: {
      {
          userId : 09A09IQMSLDK0912,
          friendId: 09A09IQMSLDAEAQS
      }
   }
  </code></pre>
  
  <p>Thanks for the advice!</p>