I am trying to do a simple calculation on two Joomla custom fields in a module. I get the article ID as a variable and want to put this in the WHERE clause to get the right custom field value. Have tried many thing, but can't manage. The field_id is 4 of the field I need and when I fill in the article ID as a number, it is working, but I can't get the variable to work (which I need so the module uses the article ID). Hope somebody can help me out?
$article_id = JFactory::getApplication()->input->get('id');
$db = JFactory::getDbo();
$query = $db->getQuery(true);
$query->select('value', 'item_id', 'field_id')
->from ($db->quoteName('#__fields_values'))
->where($db->quoteName('#__fields_values.field_id=4'))
->where($db->quoteName('#__fields_values.item_id')=$article_id);
$db->setQuery($query);
$result = $db->loadResult();
return $result;
Thanks!