$em    = $this->get('doctrine.orm.entity_manager');
$dql   = "SELECT a FROM AcmeMainBundle:Article a WHERE a.showing = 1 ORDER BY createdAt DESC";
$query = $em->createQuery($dql);

$paginator  = $this->get('knp_paginator');
$pagination = $paginator->paginate(
    $query, /* query NOT result */
    $request->query->getInt('page', 1)/*page number*/,
    10/*limit per page*/
);

$em    = $this->get('doctrine.orm.entity_manager');
    $dql   = "SELECT a FROM AcmeMainBundle:Article a WHERE a.showing = 1 ORDER BY createdAt DESC";
    $query = $em->createQuery($dql);
    $results = $query->getResults();

$em    = $this->get('doctrine.orm.entity_manager');
$dql   = "SELECT a FROM AcmeMainBundle:Article a WHERE a.showing = 1 ORDER BY createdAt DESC";
$query = $em->createQuery($dql);