Using left join with query builder doctrine - symfony

Question

Having some problems retrieving ManytoOne relationships when using left join.
Before was using this query to query for conferences
$qb = $this->createQueryBuilder('u')
->select('u.id,u.comment,
IDENTITY(u.place) AS place_id,
IDENTITY(u.sponsor) AS sponsor_id,
IDENTITY(u.tour) AS tour_id,
u.startat
');
Now I'm trying to left join with diffusion which is tied to the diffusion in a many to many relationship.
$qbt = $this->createQueryBuilder('u')
->select('u','c')
->from('AppBundle:Conference', 'p')
->leftJoin('p.diffusion', 'c');
However this query doesn't return the u.place, u.sponsor and u.tour which are ManyToOne relationships.

Answer 1

leftJoin must be followed by 'WITH'. So for example:
->leftJoin('p.diffusion', 'p', 'WITH', 'p.user=u.id', 'u.id');
But i think it's better to post both your entities so i can give you the exact answer.

Answer 2

Found the issue , I had to add
->setHint(\Doctrine\ORM\Query::HINT_INCLUDE_META_COLUMNS, true)
to the getQuery , because getArrayResults by default doesn't return foreign keys( the place, sponsor and tour respectivly).
Here is my final query in the conference repository
$qbt = $this->_em->createQueryBuilder();
$qbt->select('conference','diffusion')
->from('AppBundle:Conference', 'conference')
->leftJoin('conference.diffusion', 'diffusion');
return $qbt
->getQuery()
->setHint(\Doctrine\ORM\Query::HINT_INCLUDE_META_COLUMNS, true)
->useQueryCache(true)
->useResultCache(true,3600)
->getArrayResult();