Using fetch="EAGER" to cut down on trips to the database

AbstractContent.php

<?php

namespace Acme\ContentBundle\Entity;

use Doctrine\ORM\Mapping as ORM;

/**
 * @ORM\Entity(repositoryClass="Acme\ContentBundle\Entity\AbstractContentRepository")
 * @ORM\Table(name="content")
 * @ORM\HasLifecycleCallbacks
 * @ORM\InheritanceType("JOINED")
 * @ORM\DiscriminatorColumn(name="discr", type="string")
 * @ORM\DiscriminatorMap({"artwork"="Acme\ArtworkBundle\Entity\Artwork"})
 */
abstract class AbstractContent {
    
    /**
     * @var integer $id
     *
     * @ORM\Column(name="id", type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    protected $id;
    
    /**
     * @ORM\Column(type="string", length=255, nullable=false)
     */
    protected $type;
    
    public function __construct() {
        
    }
    
    /**
     * Get id
     *
     * @return integer 
     */
    public function getId()
    {
        return $this->id;
    }
}

ArtworkRepository.php

<?php

namespace Acme\ArtworkBundle\Entity;

use Doctrine\ORM\Mapping as ORM;

use Acme\ArtworkBundle\Entity\Date;
use Acme\ContentBundle\Entity\AbstractContent;

/**
 * @ORM\Table(name="artwork")
 * @ORM\Entity(repositoryClass="Acme\ArtworkBundle\Entity\ArtworkRepository")
 * @ORM\HasLifecycleCallbacks 
 */
class Artwork extends AbstractContent {
    
    /**
     * @var string $date
     *
     * @ORM\ManyToOne(targetEntity="Date", inversedBy="artwork", cascade={"persist"}, fetch="EAGER")
     * @ORM\JoinColumn(name="date", referencedColumnName="id")
     */
    private $date;
    
    public function __construct() {
        parent::__construct();
        $this->type = 'artwork';
    }
    
    /**
     * Set date
     *
     * @param Acme\ArtworkBundle\Entity\Intention $date
     * @return Artwork
     */
    public function setDate(\Acme\ArtworkBundle\Entity\Date $date = null) {
        $this->date = $date;
        return $this;
    }

    /**
     * Get date
     *
     * @return Acme\ArtworkBundle\Entity\Date
     */
    public function getDate()
    {
        return $this->date;
    }

}