How to make a DQL request that takes entity only if they are related to another entity with ManyToMany?

Question

I have my User linked to Event entity. Basically, users may wanna go to several events and, through a many to many, I'm registering who want to go to X event.

I need to build a Query with Doctrine that pick up users if they are available (available set to 1) OR if they plan on going to an event depending on their location ( I got this one too ). The first conditions is fine. But for the second one, I need to make sure that the user has at least one event he wants to go to, registered in the many to many relation: eventNotified.

In Php I would do a foreach loop and then condition if the $user->getEventNotified() is not an empty array ( or null ) but that would make me pull up too many results. I want to select it with SQL or DQL

How can I do that?

Here is what I have achieved so far, I just need to add a OR condition if the user wants to go an event (is eventNotified not null ?):

//We only want to return users nearby who are available OR who 
    $qb = $this->_em->getRepository( 'Entity\User' )->createQueryBuilder('a');

    $qb->andwhere( 'a.latitude > :minLat' );
    $qb->andWhere( 'a.latitude < :maxLat' );
    $qb->andWhere( 'a.longitude > :minLng' );
    $qb->andWhere( 'a.longitude < :maxLng' );
    $qb->andWhere( 'a.available = 1' );

    $qb->add( 'orderBy', $qb->expr()->sum( 'a.latitude - :lat', 'a.longitude - :lng' ));

    $array = array(
         'minLat' => $minLat,
         'maxLat' => $maxLat,
         'minLng' => $minLng,
         'maxLng' => $maxLng,
         'lat'    => $lat,
         'lng'    => $lng
    );

    $qb->setParameters( $array );

    // $qb->setFirstResult( $offset );
 //    $qb->setMaxResults( $limit );

    // print_r(array(
    //     'sql'        => $qb->getQuery()->getSQL(),
    //     'parameters' => $qb->getQuery()->getParameters(),
    // ));
    $usersNearby = $qb->getQuery()->getResult();

    return $usersNearbt;

And here is my user entity:

class User
{
    /**
     * @var integer
     *
     * @ORM\Column(name="id", type="integer", nullable=false, unique=true)
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="IDENTITY")
     */
    private $id;

    /**
     * @var integer
     *
     * @ORM\Column(name="fb_id", type="bigint", nullable=false, unique=true)
     */
    private $fb_id;

    /**
     * @var string
     *
     * @ORM\Column(name="firstname", type="string", length=100, nullable=false, unique=false)
     */
    private $first_name;

    /**
     * @var string
     *
     * @ORM\Column(name="lastname", type="string", length=100, nullable=true, unique=false)
     */
    private $last_name;

    /**
     * @var string
     *
     * @ORM\Column(name="email", type="string", length=255, nullable=true, unique=true)
     */
    private $email;

    /**
     * @var integer
     *
     * @ORM\Column(name="notation", type="integer", nullable=true, unique=true)
     */
    private $notation;

    /**
     * Bidirectional - Many users have Many favorite comments (OWNING SIDE)
     *
     * @var \Doctrine\Common\Collections\Collection
     *
     * @ORM\ManyToMany(targetEntity="Entity\Category", inversedBy="userInterests")
     */
    private $interests;

    /**
     * @var \Doctrine\Common\Collections\Collection
     *
     * @ORM\ManyToMany(targetEntity="Entity\User", cascade={"persist"})
     * @ORM\JoinTable(name="friends",
     *      joinColumns={@ORM\JoinColumn(name="user_id", referencedColumnName="id")},
     *      inverseJoinColumns={@ORM\JoinColumn(name="friend_user_id", referencedColumnName="id")}
     *      )
     **/
    private $friends;

    /**
     * @var \Doctrine\Common\Collections\Collection
     *
     * @ORM\OneToMany(targetEntity="Entity\Request", mappedBy="user", cascade={"remove"}, orphanRemoval=true)
     * @ORM\JoinColumn(nullable=true)
     */
    private $requests;

    /**
     * @var \Doctrine\Common\Collections\Collection
     *
     * @ORM\OneToMany(targetEntity="Entity\Request", mappedBy="friend", cascade={"remove"}, orphanRemoval=true)
     * @ORM\JoinColumn(nullable=true)
     */
    private $notifications;

    /**
     * Bidirectional - Many users have notified they want to go to different events (OWNING SIDE)
     *
     * @var \Doctrine\Common\Collections\Collection
     *
     * @ORM\ManyToMany(targetEntity="Entity\Event", inversedBy="userNotified", cascade={"persist"})
     */
    private $eventNotified;

    /**
     * @var integer
     *
     * @ORM\Column(name="age", type="integer", length=3, nullable=true, unique=false)
     */
    private $age;

    /**
     * @var string
     *
     * @ORM\Column(name="description", type="text", nullable=true, unique=false)
     */
    private $description;

    /**
     * @var string
     *
     * @ORM\Column(name="picture", type="string", length=300, nullable=true, unique=false)
     */
    private $picture;

    /**
     * @var string
     *
     * @ORM\Column(name="genre", type="string", length=10, nullable=true, unique=false)
     */
    private $genre;

    /**
     * @var boolean
     *
     * @ORM\Column(name="isregistered", type="boolean", length=1, nullable=false, unique=false)
     */
    private $registered;

    /**
     * @var string
     *
     * @ORM\Column(name="latitude", type="decimal", length=64, precision=25, scale=20, nullable=true, unique=false)
     */
    private $latitude;

    /**
     * @var string
     *
     * @ORM\Column(name="longitude", type="decimal", length=64, precision=25, scale=20, nullable=true, unique=false)
     */
    private $longitude;

    /**
     * @var \Entity\Security_Key
     *
     * @ORM\OneToOne(targetEntity="Entity\Security_Key", cascade={"persist","remove"}, orphanRemoval=true)
     * @ORM\JoinColumns({
     *   @ORM\JoinColumn(name="private_key_id", referencedColumnName="id", unique=true, onDelete="SET NULL")
     * })
     */
    private $private_key;

    /**
     * @var boolean
     *
     * @ORM\Column(name="isavailable", type="boolean", length=1, nullable=false, unique=false)
     */
    private $available = 0;
...

---

EDIT:

Thanks to the solution below I had it working with a little tweak ( and a few optimisations ):

    $qb = $this->getEntityManager()->createQueryBuilder();

    $qb->select( 'USER', 'EVENT', 'c', 'p' )
        ->from( 'Entity\User',  'USER' )
        ->innerJoin( 'USER.eventNotified', 'EVENT' )
        ->leftJoin( 'EVENT.categories', 'c' )
        ->leftJoin( 'EVENT.place', 'p' )
        ->add('where', $qb->expr()->andX(
                $qb->expr()->between('USER.latitude', ':minLat', ':maxLat'),
                $qb->expr()->between('USER.longitude', ':minLng', ':maxLng')
            )
        )
        ->add( 'orderBy', $qb->expr()->sum( 'USER.latitude - :lat', 'USER.longitude - :lng' ) );

    $array = array(
         'minLat' => $minLat,
         'maxLat' => $maxLat,
         'minLng' => $minLng,
         'maxLng' => $maxLng,
         'lat'    => $lat,
         'lng'    => $lng
    );

    $qb->setParameters( $array );

    $usersNearby = $qb->getQuery()->getResult();

Answer 1

You need to join to the ManyToMany entity. If the user hasn't got any Event related (by your User.eventNotified property), he/she won't be retrieved. I also would build the where conditions using the Expr class ofered by QueryBuilder:

$qb = $this->getEntityManager()->createQueryBuilder();

$qb->select( 'USER' )
    ->from( 'Entity\User',  'USER' )
    ->innerJoin( 'USER.eventNotified' )
    ->where( 
        $qb->expr()->andX(
            $qb->expr()->gt( 'USER.latitude', ':minLat' ),
            $qb->expr()->lt( 'USER.latitude', ':maxLat' ),
            $qb->expr()->gt( 'USER.longitude', ':minLng' ),
            $qb->expr()->lt( 'USER.longitude', ':maxLng' ),
            $qb->expr()->eq( 'USER.available', 1 )
        )
    ); 

(...) //orderBy and parameters

Check the QueryBuilder documentation.