title: Doctrine mapping a single entity class to multiple tables without inheritance
body: <p>Is it possible somehow to map a single entity class to two different tables without inheritance?</p>
  
  <p>Something like:</p>
  
  <pre><code>&lt;entity name="Acme\Entity\Service" table="organization_service"&gt;
      ...
      &lt;many-to-one field="target" target-entity="Acme\Entity\Organization" inversed-by="services"&gt;
          &lt;join-columns&gt;
              &lt;join-column name="target_id" referenced-column-name="id" /&gt;
          &lt;/join-columns&gt;
      &lt;/many-to-one&gt;
  &lt;/entity&gt;
  
  &lt;entity name="Acme\Entity\Service" table="person_service"&gt;
      ...
      &lt;many-to-one field="target" target-entity="Acme\Entity\Person" inversed-by="services"&gt;
          &lt;join-columns&gt;
              &lt;join-column name="target_id" referenced-column-name="id" /&gt;
          &lt;/join-columns&gt;
      &lt;/many-to-one&gt;
  &lt;/entity&gt;
  </code></pre>
  
  <p>where entity classes could look like:</p>
  
  <pre><code>class Service
  {
      ...
  
      /**
       * @var Person|Organization
       */
      private $target;
  }
  
  class Person
  {
      ...
  
      /**
       * @var Service[]
       */
      private $services;
  }
  
  class Organization
  {
      ...
  
      /**
       * @var Service[]
       */
      private $services;
  }
  </code></pre>
  
  <p>A workaround I've found so far is to create two classes PersonService and OrganizationService with the same content and map them to "person_service" and "organization_service" tables accordingly.</p>