function getChildren( VF_Level $entity )
{
if($this->getSchema()->isGlobal($entity->getType()) && $this->getSchema()->getRootLevel() != $entity->getType())
{
throw new Exception('ambiguous operation');
}
if( $entity->getNextLevel() == '' )
{
throw new Exception( 'this type doesnt have children' );
}
$nextLevelsTable = $this->getSchema()->levelTable($entity->getNextLevel());
$q = $this->getReadAdapter()->select()
->from(array('l'=>$nextLevelsTable))
->joinLeft(array('d'=>$this->getSchema()->definitionTable()), 'l.id = d.' . $entity->getNextLevel() . '_id', array())
->where('d.' . $entity->getType() . '_id = ?', $entity->getId() )
->order('title')
->group('l.id');
$r = $this->query( $q );
$children = array();
foreach( $r->fetchAll( Zend_Db::FETCH_OBJ ) as $row )
{
$child = $entity->createEntity( $entity->getNextLevel() );
$child->setId( $row->id );
$child->setTitle( $row->title );
$children[] = $child;
}
return $children;
}
