title: Retrieve results from regexp_matches as one row
body: <p>So, if have this string <code>aassdd</code></p>
  
  <p>This code:</p>
  
  <p><code>regexp_matches('aassdd', 'a', 'g')</code></p>
  
  <p>returns 2 different rows.</p>
  
  <p>It is possible to retrieve all matches as one row? for example as <code>array</code> type as one row, that is from code above, needed result is: <code>{a,a}</code></p>