use Doctrine\ORM\Query;

use Doctrine\ORM\QueryBuilder;

use Doctrine\ORM\NoResultException;

        ->createQuery("SELECT doctag FROM WikiTagBundle:DocumentTag doctag JOIN doctag.document doc WHERE doc.externalId=:doc_id ORDER BY doctag.tagOrder ASC")

        ->setParameter("doc_id", strval($doc_id))

        ->createQuery("SELECT MAX(doctag.tagOrder) FROM WikiTagBundle:DocumentTag doctag JOIN doctag.document doc WHERE doc.externalId= :doc_id")

        ->setParameter("doc_id", strval($doc_id))

    /**

     *

     * Enter description here ...

     * @param unknown_type $external_id

     * @param array $filter_array

     * @return QueryBuilder

     */

    private function createQueryBuilderByDocumentExternalId($external_id, array $filter_array=null) {

        $qb = $this->createQueryBuilder("dt")

        ->join('dt.document', 'd')

        ->where('d.externalId = :external_id');

        $params = array("external_id"=>strval($external_id));

        if(!is_null($filter_array)) {

            foreach ($filter_array as $key => $value) {

                $qb = $qb->where("dt.$key = :p_$key");

                $params["p_$key"] = $value;

            }

        }

        $qb = $qb->setParameters($params);

        return $qb;

    }

    public function findByDocumentExternalId($external_id, array $filter_array=null)

    {

        $qb = $this->createQueryBuilderByDocumentExternalId($external_id, $filter_array);

        return $qb->getQuery()->getResult();

    }

    public function findOneByDocumentExternalId($external_id, array $filter_array=null) {

        $qb = $this->createQueryBuilderByDocumentExternalId($external_id, $filter_array)->setMaxResults(1);

        try {

            return $qb->getQuery()->getSingleResult();

        } catch (NoResultException $e) {

            return null;

        }

    }