title: How to get timestamp associated with percentile(x) value using timescale db time_bucket
body: <p>I need find percentile(50) value and its timestamp using timescale db time-bucket. Finding P50 is easy but I don't know how to get the time stamp.</p>
  <pre><code>    Select time_bucket('120 sec',timestamp_utc) as interval_size,
      
      first(timestamp_utc,int_val) as minTime,
      min(int_val) as minVal,
          
      last(timestamp_utc,int_val) as maxTime,
      max(int_val) as maxVal,
      
      -- timestamp of percentile value below.
      percentile_disc(0.5) within group (order by int_val) as medianVal
              
      from timeseries.raw
      where timestamp_utc &gt; NOW() - INTERVAL '10 min'
      AND tag_id = 59560544877390423
      group by interval_size
      order by interval_size desc
  </code></pre>