使用Doctrine2和PostgreSQL，我需要创建外键约束DEFERRABLE和INITIALLY DEFERRED
在Doctrine/DBAL/Platforms/PostgreSqlPlatform.php中找到选项“deferrable”和“deferred”，但不知道在Entity注解中的何处使用它

<?php 
/**
 * Class User
 *
 * @ORM\Table(name="jira_issues_changelogs")
 * @ORM\Entity
 * @package JiraBundle\Entity\Issue
 */
class Changelog
{
    /**
     * @var string
     *
     * @ORM\Column(name="id", type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="NONE")
     */
    protected $id;

    /**
     * @ORM\ManyToOne(targetEntity="\JiraBundle\Entity\Issue", inversedBy="changelog")
     * @ORM\JoinColumn(name="issue", referencedColumnName="id")

     Need this column foreign key to be DEFERRABLE INITIALLY DEFERRED

     */
    protected $issue;

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