title: How to set intervalstyle = iso_8601 and then run a select query in golang
body: <p>I have a table with an <code>interval</code> column, something like this.</p>
  
  <pre><code>CREATE TABLE validity (
    window INTERVAL NOT NULL
  );
  </code></pre>
  
  <p>Assume the value stored is 'P3DT1H' which is in <code>iso_8601</code> format.
  When I try to read the value, it comes in regular postgres format. </p>
  
  <pre><code>3 days 01:00:00
  </code></pre>
  
  <p>However I want the value in <code>iso_8601</code> format. How can I achieve it? </p>