List Entities Action

CompanyController.php

public function listEntitiesAction(Request $request)
    {       
        $entity = $request->query->get('entity');
        $table = $request->query->get('table');
        $repository = $this->getDoctrine()->getRepository('AALCOCompanyBundle:' . $entity);
        $metadata = $this->getDoctrine()->getEntityManager()->getClassMetadata('AALCOCompanyBundle:' . $entity);
        $qb = $repository->createQueryBuilder($table);
        $dataTable = new Datatable(
            $request->query->all(),
            $repository,
            $metadata,
            $this->getDoctrine()->getEntityManager(),
            $qb
        );
        if ($entity == 'Branch') { $dataTable->setJoinType('parent.branch_name', Datatable::JOIN_LEFT); }
        if ($entity == 'User') { $dataTable->setJoinType('parent.full_name', Datatable::JOIN_LEFT); }
        $dataTable->makeSearch();
        
        $view = $this->view($dataTable->getSearchResults(), 200)
                ->setFormat('json')
                ;
 
        return $this->get('fos_rest.view_handler')->handle($view);
    }

Datatable.php

public function __construct(array $request, EntityRepository $repository, 
            ClassMetadata $metadata, EntityManager $em, QueryBuilder $qb)
    {
        $this->em = $em;
        $this->request = $request;
        $this->repository = $repository;
        $this->metadata = $metadata;
        $this->tableName = Container::camelize($metadata->getTableName());
        $this->defaultJoinType = self::JOIN_INNER;
        $this->setParameters();
        $this->qb = $qb;
        $this->echo = $this->request['sEcho'];
        $this->search = $this->request['sSearch'];
        $this->offset = $this->request['iDisplayStart'];
        $this->amount = $this->request['iDisplayLength'];
    }

Error

request: Doctrine\ORM\Query\QueryException: [Semantical Error] line 0, col 356 near 'Branches INNER': Error: 'Branches' is already defined. (uncaught exception) at /media/sf_sandbox/aalcodev/vendor/doctrine/orm/lib/Doctrine/ORM/Query/QueryException.php line 49