title: How to validate a "select" multiple of bootstrap with codeigniter
body: <p>Hi sorry for my poor English, I'm from Argentina.</p>
  
  <p>I Search the web some similar theme but did not find any.
  I am creating a web application and I'm using boostrap from FrontEnd and codeigniter for BackEnd. Also I'm using a custom for bootstrap for "selects", this is the link: <a href="http://silviomoreto.github.io/bootstrap-select/" rel="nofollow">http://silviomoreto.github.io/bootstrap-select/</a></p>
  
  <p>In the view I have this code:</p>
  
  <pre><code>&lt;div class="form-group"&gt;
  &lt;?php echo form_label('Languages ​​supported', 'lang'); ?&gt;
  &lt;?php $options = array('Ingles' =&gt; 'Ingles','Español' =&gt; 'Español', 'Portugués' =&gt; 'Portugués', 'Ruso' =&gt; 'Ruso', 'Francés' =&gt; 'Francés', 'Alemán' =&gt; 'Alemán', 'Italiano' =&gt; 'Italiano'); $attribute ='class="selectpicker show-tick form-control" multiple title="Seleccione los lenguajes..."'; echo form_dropdown('lang', $options, 'title',$attribute); ?&gt;
  </code></pre>
  
  <p></p>
  
  <p>This in the browser looks like this:
  <a href="http://www.subeimagenes.com/img/captura-1052187.PNG" rel="nofollow">View image</a></p>
  
  <p>For validation I have this code:</p>
  
  <pre><code>$this-&gt;form_validation-&gt;set_rules('lang', 'Idiomas', 'trim|required|min_length[1]|max_length[50]|xss_clean');
  </code></pre>
  
  <p>But in the database, only one value is saved. For example: In the picture above, a user selected three values ​​(Spanish, French and Portuges) but in the database only the first value that is stored (Spanish)
  How to make the all values is saved in the database</p>