Запрос из трех таблиц - Разработка расширений для Joomla

$query = $db->getQuery(true);
$query->select('m.user_id,m.about,u.name')
	->from('#__portfolio_members AS m')
	->leftJoin('#__users AS u ON m.user_id = u.id');
$p_list = $db->setQuery($query)->loadObjectList();

foreach ($p_list as $var) 
{
	//достаем фото пользователя
	$query = $db->getQuery(true);
	$query->select('avatar');
	$query->from('#__community_users');
	$query->where("userid = {$var->user_id}");
	$db->setQuery($query) or die("запрос1 не сработал"); 
	$avatar = $db->loadResult();
}

$query = $db->getQuery(true);
$query->select('m.user_id,m.about,u.name,c.avatar')
	->from('#__portfolio_members AS m')
	->leftJoin('#__users AS u ON m.user_id = u.id');
	->leftJoin('#__community_users AS c ON m.user_id = c.userid');
$p_list = $db->setQuery($query)->loadObjectList();

$query->limit('0,40');

$query
->select(array('a.id', 'a.name', 'a.created', 'a.title', 'a.text', 'ROUND(a.rating_sum / a.rating_count, 2) AS rating_value', 'a.rating_count', 'a.hits', 'a.catid', 'a.cat_title', 'COUNT(b.itemID) AS count'))
 ->from('#__contents_item AS a')
->join('INNER', '#__contents_comments AS b ON (a.id = b.itemID)')
->where('a.published=1')
->where('a.catid LIKE '.$this->input->getInt('id'));

$query
->select(array('a.id', 'a.name', 'a.created', 'a.title', 'a.text', 'ROUND(a.rating_sum / a.rating_count, 2) AS rating_value', 'a.rating_count', 'a.hits', 'a.catid', 'a.cat_title', 'COUNT(*) AS count'))
 ->from('#__contents_item AS a')
->join('INNER', '#__contents_comments AS b ON (a.id = b.itemID)')
->where('a.published=1')
->where('a.catid LIKE '.$this->input->getInt('id'))
->group('a.id');

$db = JFactory::getDbo();
$query = $db->getQuery(true);
$query->select('u.user_id, u.content_id, u.section_pk, u.setevoy_proekt, u.konkurs, u.date, r.region, a.name')
	  ->from('#__planeta_pk_users AS u')
	  ->leftJoin('#__planeta_regions AS r ON r.id = u.region');
	  ->leftJoin('#__users AS a ON a.id = u.user_id');

...
$query->select('..., s.title, k.title')
->from('#__users AS u')
...
->leftJoin('#__content AS s ON s.id = u.proekt')
->leftJoin('#__content AS k ON k.id = u.konkurs')
...
echo $user->title;

$query->select('..., s.title AS title1, k.title AS title2')
echo $user->title1;
echo $user->title2;