title: Multiple many to many relationships in symfony2
body: <p>I have 3 entities:</p>
  
  <ul>
  <li>Song</li>
  <li>Artist</li>
  <li>Genre</li>
  </ul>
  
  <p>One song can have multiple genres and vice versa. A song can also have multiple artists and vice versa.</p>
  
  <p>That's why I'm trying to create two many-to-many relationships. However, when generating the Entity clases, the first of the two is always 'overridden' by the second one and no variable or accessors are created for that one..</p>
  
  <p>Here's my yaml: <strong>(updated)</strong></p>
  
  <pre><code>Foo\BarBundle\Entity\Song:
    type: entity
    table: song
    id:
      id:
        type: integer
        generator:
          strategy: AUTO
    fields:
      title:
        type: string
        length: 300
      mime_type:
        type: string
        length: 20
      filesize:
        type: integer
        length: 20
      length:
        type: string
        length: 20
      created_at:
        type: datetime
        gedmo:
          timestampable:
            on: create
    manyToOne:
      user:
        targetEntity: Spotaset\UserBundle\Entity\User
        inversedBy: songs
    manyToMany:
      genres:
        targetEntity: Genre
        inversedBy: songs
    manyToMany:
      artists:
        targetEntity: Artist
        inversedBy: songs
  
  
  Foo\BarBundle\Entity\Artist:
    type: entity
    table: artist
    id:
      id:
        type: integer
        generator:
          strategy: AUTO
    fields:
      name:
        type: string
        length: 100
        unique: true
    manyToMany:
      songs:
        targetEntity: Song
        mappedBy: artistss
  
  Foo\BarBundle\Entity\Genre:
    type: entity
    table: genre
    id:
      id:
        type: integer
        generator:
          strategy: AUTO
    fields:
      name:
        type: string
        length: 100
        unique: true
    manyToMany:
      songs:
        targetEntity: Song
        mappedBy: genres
  </code></pre>
  
  <p>I don't know a lot about relational databases so I don't know wether this is a bug or that this design is just bad in general..</p>
  
  <p>All help is greatly appreciated!</p>