public function join($query)
    {
        $clause = '';
        $repository = $query->getRepository();
        $resources = $repository->getResources();
        $links = $resources->getLinks();
        foreach ($links as $link) {
            $type = strtoupper($link->resource->getLinkType());
            switch ($type) {
                case 'STRONG' : $type = 'INNER';break;
                case 'WEAK'   : $type = 'LEFT'; break;
            }
            $query->join($type, $link->resource->getName().' AS '.$this->_store->quoteName($link->resource->getAlias()), array(
                $link->child.'='.$link->parent,
            ));
        }

        $this->_links($query, $query->link);

        if (!empty($query->join)) {
            $joins = array();
            foreach ($query->join as $join) {
                $tmp = '';

                if (!empty($join['type'])) {
                    $tmp .= $join['type'].' ';
                }

                $tmp .= 'JOIN '.$join['resource'];
                $tmp .= ' ON '.implode(' AND ', $join['condition']);

                $joins[] = $tmp;
            }

            $clause = implode(' ', $joins);
        }

        return $clause;
    }