$result=db_query('SELECT DISTINCT(n.nid), n.title, b.parent FROM {node} n '.node_access_join_sql().' INNER JOIN {book} b ON n.nid = b.nid WHERE n.status = 1 AND '.node_access_where_sql().' ORDER BY b.weight, n.title');
$result=db_query('SELECT DISTINCT(n.nid), n.title, b.parent FROM {node} n '.node_access_join_sql().' INNER JOIN {book} b ON n.nid = b.nid WHERE n.status = 1 AND '.node_access_where_sql().' ORDER BY b.weight, n.title');