title: Azure Stream Analytics Job - Cumulative sum in fixed 1 hour window
body: <p>I'm currently working on a requirement for a real-time dashboard using steam analytics with a power bi output. The user would like to see a cumulative sum of an amount for the current hour. This would revert back to 0 at the beginning of the next hour.</p>
  
  <p>From my understanding a Tumbling window should do this but the value doesn't change in the Power BI dashboard. </p>
  
  <p>Any help would be appreciated!</p>
  
  <p>Example:</p>
  
  <pre><code>SELECT System.Timestamp AS Timestamp,
     SUM(Revenue) AS Revenue
  INTO [TotalRevenuePerHour]
  FROM [Input]
  GROUP BY TUMBLINGWINDOW(hour,1)
  </code></pre>