title: What is the best way to show reports with firebase?
body: <p>I am currently using Cloud Functions to do aggregation in Firebase so that whenever a certain type of data entry occurs, I aggregate it accordingly and store it to show our reports. There are following concerns with this approach:-</p>
  
  <ol>
  <li>Adding new reports would mean going over all the existing data and that could be expensive with firebase realtime database</li>
  <li>Making any changes to existing reports is also non-trivial</li>
  </ol>
  
  <p>I was considering a solution like Cloud Dataflow. However, one issue is that it is not part of the Spark or Flame plan of Firebase.</p>
  
  <p><strong>What is the best way to handle reporting with firebase, keeping both cost and performance in mind?</strong></p>