/**
  * @see	\wcf\system\cronjob\ICronjob::execute()
  */
 public function execute(Cronjob $cronjob)
 {
     parent::execute($cronjob);
     // delete orphaned attachments
     $attachmentIDs = array();
     $sql = "SELECT\tattachmentID\n\t\t\tFROM\twcf" . WCF_N . "_attachment\n\t\t\tWHERE\tobjectID = ?\n\t\t\t\tAND uploadTime < ?";
     $statement = WCF::getDB()->prepareStatement($sql);
     $statement->execute(array(0, TIME_NOW - 86400));
     while ($row = $statement->fetchArray()) {
         $attachmentIDs[] = $row['attachmentID'];
     }
     if (!empty($attachmentIDs)) {
         AttachmentEditor::deleteAll($attachmentIDs);
     }
 }