title: Firestore - What is best data structure for my scenario?
body: <p>I am struggling with an optimal schema for my app. Should I go with top level collections, sub-collections, arrays, etc. </p>
  
  <p>Setup:</p>
  
  <ol>
  <li>My app will have many quizzes that users will participate in.</li>
  <li>Each quiz will have multiple questions.</li>
  <li>Each question will have multiple answers, only one can be chosen.</li>
  <li>Each user will answer each quiz only once.</li>
  </ol>
  
  <p>Requirements:</p>
  
  <ol>
  <li>I need to store responses for each user and be able to report at user level.</li>
  <li>I need to see aggregate results for each quiz, for each question, number of answers.</li>
  </ol>
  
  <p>Any help is appreciated.</p>