title: Index write costs
body: <p>Here <a href="https://cloud.google.com/appengine/docs/standard/java/datastore/entities#Java_Understanding_write_costs" rel="nofollow noreferrer">Java Understanding write costs</a> I was reading about optimizing my entities.</p>
  
  <p>What I don't understand in the first line is </p>
  
  <blockquote>
    <p>When your application executes a Cloud Datastore put operation</p>
  </blockquote>
  
  <p>I'm using NodeJs and the <a href="https://cloud.google.com/nodejs/docs/reference/datastore/1.3.x/Datastore" rel="nofollow noreferrer">NodeJs documentation</a> mentions no put command, hence I'm confused if the extra index write costs only applies to the Insert command or also to other commands like Update.</p>
  
  <p><strong>Update</strong>
  I found this answer <a href="https://stackoverflow.com/questions/36509760/google-datastore-new-pricing-effect-operations">Google Datastore new pricing effect operations</a>
  from what I understand it doesn't matter if I let datastore automatically index my properties since I'm only charged once for each time an entity is inserted, updated and read.</p>
  
  <p>I guess the only improvement I get by excluding indexes on some properties is decreased storage requirements?</p>