public function findWbChallengeForAutocomplete($title,$offset,$limit) {
		if ($offset<=-1){
			return null;
		}
		$em=$this->getEntityManager();
		$qb=$em->createQueryBuilder();
		$qb->select("p")->from("ApplicationChallengerzBundle:WbChallenge","p")
							->where("p.title like:title")
							->orderBy("p.title","ASC")
							->setParameter("title",$title)
							->setFirstResult($offset)
							->setMaxResults($limit);
		}

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