public static function getClauses($nid)
 {
     $dbm = \CADB\DBM::instance();
     $que = "SELECT id,parent,idx,subject FROM {guide_clause} WHERE nid = " . $nid . " ORDER BY parent ASC, idx ASC";
     $_clauses = array();
     while ($row = $dbm->getFetchArray($que)) {
         $clauses[] = \CADB\Guide::fetchGuideClause($row);
     }
     return $clauses;
 }