private function __construct()
 {
     try {
         self::$instance = new PDO('oci:dbname=FISHEYE.WORLD;charset=UTF8', 'FISHEYECNS', 'FISHEYECNS');
         self::$instance->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
     } catch (Exception $e) {
         echo 'Erreur : ' . $e->getMessage() . '<br />';
         echo 'N° : ' . $e->getCode();
         // phpinfo();
     }
 }