Symfony: How do I annotate entity properties that are objects to get Doctrine to store a foreign key?
===

I'm still getting to grips with Symfony and Doctine and I appreciate this might sound overly simple.

I have at present two basic entities: `WebSite` (having `id` and `canonicalUrl` properties) and `Job` which has, as one property, a `WebSite`. Both are under the same namespace. Relevant here is the `Job` entity:
    
    /**
     * 
     * @ORM\Entity
     */
    class Job
    {
        /**
         * 
         * @var integer
         * 
         * @ORM\Id
         * @ORM\Column(type="integer")
         * @ORM\GeneratedValue(strategy="AUTO")
         */
        protected $id;
        
        /**
         *
         * @var WebSite
         */
        protected $website;
    }

In database terms, a persisted `Job` should be storing the `id` of the relevant `WebSite`.

Without any changes to the above, calling `php app/console doctrine:migrations:diff` generates a new migration for a table named `Job` with a single `id` field.

How do I annotate `Job::website` such that Doctrine knows to create an integer field and to get the value as the `id` of the `Website` object?