Doctrine2: Best way to handle many-to-many with extra columns in reference table

Question

I\'m wondering what\'s the best, the cleanest and the most simply way to work with many-to-many relations in Doctrine2.

Let\'s assume that we\'ve got an album like

Answer 1

You may be able to achieve what you want with Class Table Inheritance where you change AlbumTrackReference to AlbumTrack:

class AlbumTrack extends Track { /* ... */ }

And getTrackList() would contain AlbumTrack objects which you could then use like you want:

foreach($album->getTrackList() as $albumTrack)
{
    echo sprintf("\t#%d - %-20s (%s) %s\n", 
        $albumTrack->getPosition(),
        $albumTrack->getTitle(),
        $albumTrack->getDuration()->format('H:i:s'),
        $albumTrack->isPromoted() ? ' - PROMOTED!' : ''
    );
}

You will need to examine this throughly to ensure you don't suffer performance-wise.

Your current set-up is simple, efficient, and easy to understand even if some of the semantics don't quite sit right with you.