/**
  * Additional actions to take on delete
  *
  */
 public function delete($connection = null)
 {
     $this->deletePhysicalObjectRelations();
     // Delete subject relations
     $criteria = new Criteria();
     $criteria = $this->addrelationsRelatedBysubjectIdCriteria($criteria);
     if ($subjectRelations = QubitRelation::get($criteria)) {
         foreach ($subjectRelations as $subjectRelation) {
             $subjectRelation->delete();
         }
     }
     // Delete object relations
     $criteria = new Criteria();
     $criteria = $this->addrelationsRelatedByobjectIdCriteria($criteria);
     if ($objectRelations = QubitRelation::get($criteria)) {
         foreach ($objectRelations as $objectRelation) {
             $objectRelation->delete();
         }
     }
     parent::delete($connection);
     QubitSearch::deleteInformationObject($this);
 }