title: Trying to determine a good number of partitions per topic while considering the restrictions imposed by KSQL DB
body: <p>To preface, I'm a beginner to Apache Kafka - please forgive any obvious mistakes/misunderstandings in the way that I've posed this question.</p>
  <p><strong>Quick summary of what I'm trying to develop:</strong></p>
  <ul>
  <li>I'm developing an application that needs to continuously track the location of multiple users at once</li>
  <li>This application then needs to be able to use KSQL DB to query the location of these users</li>
  </ul>
  <p><strong>What I need clarification on:</strong></p>
  <ul>
  <li>Since I can only really query one topic in KSQL DB (joins are really only limited to two topics in KSQL DB), the number of topics i could have to track users would only be one. I'm hoping to correspond each partition i make in this topic to the user-id. I may have 1000s of user-ids in this single topic.</li>
  </ul>
  <p>I'm wondering what the performance issues of having thousands of partitions in this single topic might be and whether there is a better way to approach this problem?</p>
  <p>Thank you!</p>