function __construct()
 {
     mysql_base::__construct();
     $this->set_sql("SELECT * FROM member");
     $this->run_query();
     $this->set_result();
 }
 function __construct($member_id)
 {
     mysql_base::__construct();
     $this->set_sql("SELECT * FROM loan WHERE member_id='{$member_id}' AND is_lent='1'");
     $this->run_query();
     $this->set_result();
 }