title: SELECT first element of column of type list in SQL
body: <p>I have a table with a field called 'ids' that represents a list. I would like to execute a SELECT query that retrieves the first value of the list. Any ideas of what function to use, i.e. what should fn be:</p>
  
  <pre><code>SELECT fn(ids) from &lt;TABLE&gt;
  </code></pre>