title: Increment field of mysql database using codeigniter's active record syntax
body: <p>I have the following php-codeigniter script which attempts to increment a field of a record using active-record syntax:</p>
  
  <pre><code>$data = array('votes' =&gt; '(votes + 1)');
  $this-&gt;db-&gt;where('id', $post['identifier']);
  $this-&gt;db-&gt;update('users', $data);
  </code></pre>
  
  <p>This produces the following SQL:</p>
  
  <p><code>"UPDATE</code>users<code>SET</code>votes<code>= '(votes + 1)' WHERE</code>id<code>= '44'</code>"</p>
  
  <p>Which doesn't run, but this SQL does do what I'm looking for:
  <code>"UPDATE</code>users<code>SET</code>votes<code>= (votes + 1) WHERE</code>id<code>= '44'</code>"` &lt;--Note the lack of quotes around (votes + 1)</p>
  
  <p>Does anyone know how to implement this type of query with codeigniter's active record syntax?</p>