Return number of results from Doctrine query that uses createQuery - doctrine-orm

Question

$q = $this->_em->createQuery("SELECT s FROM app\models\Quest s
LEFT JOIN s.que c
WHERE s.type = '$sub'
AND c.id = '$id'");
Given a query like the one above, how would I retrieve the number of results?

Answer 1

Alternatively one can look at what Doctrine Paginator class does to a Query object to get a count (this aproach is most probably an overkill though, but it answers your question):
public function count()
{
if ($this->count === null) {
/* #var $countQuery Query */
$countQuery = $this->cloneQuery($this->query);
if ( ! $countQuery->getHint(CountWalker::HINT_DISTINCT)) {
$countQuery->setHint(CountWalker::HINT_DISTINCT, true);
}
if ($this->useOutputWalker($countQuery)) {
$platform = $countQuery->getEntityManager()->getConnection()->getDatabasePlatform(); // law of demeter win
$rsm = new ResultSetMapping();
$rsm->addScalarResult($platform->getSQLResultCasing('dctrn_count'), 'count');
$countQuery->setHint(Query::HINT_CUSTOM_OUTPUT_WALKER, 'Doctrine\ORM\Tools\Pagination\CountOutputWalker');
$countQuery->setResultSetMapping($rsm);
} else {
$countQuery->setHint(Query::HINT_CUSTOM_TREE_WALKERS, array('Doctrine\ORM\Tools\Pagination\CountWalker'));
}
$countQuery->setFirstResult(null)->setMaxResults(null);
try {
$data = $countQuery->getScalarResult();
$data = array_map('current', $data);
$this->count = array_sum($data);
} catch(NoResultException $e) {
$this->count = 0;
}
}
return $this->count;
}

Answer 2

You can either perform a count query beforehand:
$count = $em->createQuery('SELECT count(s) FROM app\models\Quest s
LEFT JOIN s.que c
WHERE s.type=:type
AND c.id=:id)
->setParameter('type', $sub);
->setParameter('id', $id);
->getSingleScalarResult();
Or you can just execute your query and get the size of the results array:
$quests = $q->getResult();
$count = count($quests);
Use the first method if you need the count so that you can make a decision before actually retrieving the objects.