title: Query Logs for filter non-empty strings in Google Cloud Logs Explorer
body: <p>I am trying to query for all logs that meets a simple condition:</p>
  <p>The <code>jsonPayload</code> of some <code>DEFAULT</code> log entries have the following structure:</p>
  <pre class="lang-js prettyprint-override"><code>response: {
      Values: [
          [   ] 
      ]
  }
  </code></pre>
  <p>where each item in <code>Values</code> is an array. In most cases, <code>Values</code> have a single item <code>&quot;&quot;</code> in the array (empty). I want to write a query that can filter all logs entry that have values different from an empty string (an array in fact).</p>
  <p>Here's the query I tried to run:</p>
  <pre><code>severity=&quot;DEFAULT&quot; AND
  jsonPayload.response.Values != ''
  </code></pre>
  <p>This did not return any result. There are thousands of entries, most of which are empty. Can this be done? If so, what am I missing in this case?</p>
  <p><strong>Edit</strong></p>
  <p>I am checking to see if the first value inside <code>Values</code> is something other than an empty string. In entries I am looking for, the value of the first item will be an array.</p>
  <p><strong>Edit 2</strong></p>
  <p>Following the reference suggested, I tried looking for the opposite:</p>
  <pre><code>severity=&quot;DEFAULT&quot; AND
  jsonPayload.response.Values = ''
  </code></pre>
  <p>This shows me the all the results with empty Values array as expected. What's confusing me is why it's not working. The logs are generated by a cloud function that serves as a webhook for event processing. The <code>jsonPayload</code> represents the body of the request from the event source.</p>