title: Influxdb - Subtracting value from previous row, group by time
body: <p>Is it possible to get individual data from cumulative?</p>
  
  <p>Output of the following query is </p>
  
  <pre><code>SELECT mean("value") FROM "statsd_value" WHERE "type_instance" = 'counts' AND time &gt; now() - 5m GROUP BY time(10s) fill(none)
  
  TimeStamp   Value
  1463393810  0
  1463393820  10
  1463393830  23
  1463393840  34
  1463393850  67
  1463393860  90
  1463393870  104
  </code></pre>
  
  <p>Basically, the above data is cumulative data, I want to get individual data from that similar to this</p>
  
  <pre><code>TimeStamp   Value
  1463393820  10
  1463393830  13
  1463393840  11
  1463393850  33
  1463393860  23
  1463393870  14
  </code></pre>
  
  <p>Is it possible to form query to get data in this way?</p>