title: what does positional and named parameter in a query mean?
body: <p>here we got a positional parameter:</p>
  
  <pre><code>SELECT 
  u 
  FROM ForumUser u 
  WHERE u.id = ?1
  </code></pre>
  
  <p>and here a named parameter:</p>
  
  <pre><code>SELECT 
  u 
  FROM ForumUser u 
  WHERE u.username = :name
  </code></pre>
  
  <p>this is DQL (doctrine query language) but i think the concept is the same.</p>
  
  <p>could someone please explain what these mean and do?</p>