title: Azure RUs on cosmosDB
body: <p>I am trying to find out how RUs are working in order to optimize the requests made to the DB.</p>
  
  <p>I have a simple query where is select by id</p>
  
  <pre><code>SELECT * FROM c WHERE c.id='cl0'
  </code></pre>
  
  <p>That query costs <code>277.08</code> RUs</p>
  
  <p>Then I have another query where I select by another property</p>
  
  <pre><code>SELECT * FROM c WHERE c.name[0].id='35bfea78-ccda-4cc5-9539-bd7ff1dd474b' 
  </code></pre>
  
  <p>That query costs <code>2.95</code> RUs</p>
  
  <p>I cant figure out why there is that a big a difference in the consumed RUs between these two queries.</p>
  
  <p>Thw two queries return the exact same result</p>
  
  <pre><code>[
      {
          "label": "class",
          "id": "cl0",
          "_id": "cl0",
          "name": [
              {
                  "_value": "C0.Iklos0",
                  "id": "35bfea78-ccda-4cc5-9539-bd7ff1dd474b"
              }
          ],
          "_rid": "6Ds6AJHyfgBfAAAAADFT==",
          "_self": "dbs/6Ds4FA==/colls/6Ds6DFewfgA=/docs/6Ds6AJHyfgBdESFAAAAAAA==/",
          "_etag": "\"00007200-0000-0000-0000-w3we73140000\"",
          "_attachments": "attachments/",
          "_ts": 1528722196
      }
  ]
  </code></pre>