CREATE OR REPLACE FUNCTION cascade_modify_time() RETURNS trigger AS $cascade_modify_time$
  BEGIN
    EXECUTE 'UPDATE ' || quote_ident(TG_ARGV[0]) || ' SET modified=CURRENT_TIMESTAMP WHERE id = NEW.' || quote_ident(TG_ARGV[1]);
    RETURN NULL;
  END;
$cascade_modify_time$ LANGUAGE plpgsql;



CREATE TRIGGER page_modify_trigger
    AFTER INSERT OR UPDATE OR DELETE ON pages FOR EACH ROW
    EXECUTE PROCEDURE cascade_modify_time('almanacs','almanac_id');