title: Observability: can we filter by tags then aggregate on prometheus or any metrics backend server
body: <p>For example, I call Redis server with following command:</p>
  
  <pre><code>SET key "value"
  </code></pre>
  
  <p>After running, I want to track those 2 information at the same time:</p>
  
  <ul>
  <li>statistic of all write operators (so tag should be SET)</li>
  <li>statistic of all specific operators (so tag should be SET and key)</li>
  </ul>
  
  <p>So I will create views for tracking metrics. There are 2 ways I can think:</p>
  
  <ul>
  <li>Single view with tag "SET" <strong>and</strong> key. and later hopefully I can filter by "SET" or by "SET" and by key. (1)</li>
  <li>Creating 2 views. First view only has tag "SET" and second view will have tags "SET" and key. So each view for each query. (2)</li>
  </ul>
  
  <p>I prefer (1) because it is more elegant and I don't need to create too many views. My question is: If I do on (1), can it works on metric backend server ? (i.e: Prometheus). Or metric backend server doesn't support filter by tag and aggregation, so I must create separate views ?</p>
  
  <p>Thanks </p>