From  this discussion.

When using the attached classes with this code :

Doctrine_Query::create()
    ->from("Episode ep")
    ->leftJoin("ep.team t")
    ->execute();

Gives the following exception :

        Fatal error:  Uncaught exception 'Doctrine_Record_Exception' with message 'Unknown property team_teamId' in /Users/ishtanzar/Sites/_library/Doctrine-0.11.1/Doctrine/Record.php:813
        Stack trace:
        #0 /Users/ishtanzar/Sites/_library/Doctrine-0.11.1/Doctrine/Record.php(1021): Doctrine_Record->rawGet('team_teamId')
        #1 /Users/ishtanzar/Sites/_library/Doctrine-0.11.1/Doctrine/Record.php(949): Doctrine_Record->coreSetRelated('team', Object(Team))
        #2 /Users/ishtanzar/Sites/_library/Doctrine-0.11.1/Doctrine/Access.php(133): Doctrine_Record->set('team', Object(Team))
        #3 /Users/ishtanzar/Sites/_library/Doctrine-0.11.1/Doctrine/Hydrator.php(225): Doctrine_Access->offsetSet('team', Object(Team))
        #4 /Users/ishtanzar/Sites/_library/Doctrine-0.11.1/Doctrine/Query/Abstract.php(999): Doctrine_Hydrator->hydrateResultSet(Object(PDOStatement), Array)
        #5 /Users/ishtanzar/Sites/test/testDoctrineRelations/index.php(16): Doctrine_Query_Abstract->execute()
        #6 {main}
          thrown in /Users/ishtanzar/Sites/_library/Doctrine-0.11.1/Doctrine/Record.php on line 813

From romanb :

all column names (not aliases) are forced to lowercase in doctrine for portability. That is, if you do: hasColumn('team_teamId as id') doctrine stores: column name = team_teamid , column alias (field name) = id. And it looks like the relation mapping does not force the given name to lowercase before looking it up, maybe it should.