title: SQL query - Group by an approximation
body: <p>I have a query: SELECT ID, Name, Distance FROM Station GROUP BY 'Distance approximation'</p>
  
  <p>In my example, Distance is a double and I would like to group all the elements with the same approximate distance together. For example, element_1 with distance 212 will be in the same group as element_2 with distance 240 but not in the same group as 300 (difference is > 50).</p>
  
  <p>Thanks</p>