title: Upsert with incrementing a value if the row exists
body: <p>I have a collection "servers" that looks like:</p>
  
  <pre><code>{"server": "234.234.34.34", "count": 1}
  </code></pre>
  
  <p>I want make this call, and if the row exists I want to just update the counter, otherwise insert with the value 'count' 1.</p>
  
  <p>Is this possible?</p>
  
  <p>I know you can upsert, but not sure how to handle an update with an increment.</p>