output.html.twig

{% for competition in competitions %}
    <tr>
        <td>{{ competition.title }}</td>
        <td>{{ competition.searchPhrase }}</td>
        <td>{{ competition.openAt|date }}</td>
        <td>{{ competition.closeAt|date }}</td>
        <td>{{ competition.total }}</td>
    </tr>
{% endfor %}

repo.php

<?php

use Doctrine\ORM\EntityRepository;

/**
 * CompetitionRepository
 *
 * This class was generated by the Doctrine ORM. Add your own custom
 * repository methods below.
 */
class CompetitionRepository extends EntityRepository
{
    public function findAllWithCount()
    {
        $qb = $this->createQueryBuilder('c');
        $qb->select('c.id, c.title, c.searchPhrase, c.openAt, c.closeAt, COUNT(e.competition) AS total, c.winnerId')
           ->leftJoin('c.entries', 'e')
           ->groupBy('c.id, c.title, c.searchPhrase, c.openAt, c.closeAt, c.winnerId, e.competition')
           ->orderBy('c.openAt');

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

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