<?php
$db = JFactory::getDbo();
$query = $db->getQuery(true);
$query->update($db->quoteName(array('rufx7_kunena_users')));
$query->set($db->quoteName('group_id')." = ".$db->quote($10));
$query->where($db->quoteName('posts')." >= ".$db->quote($100));
$query->and($db->quoteName('thankyou')." >= ".$db->quote($30));
$db->setQuery($query);
$results = $db->loadObjectList();
?>