class DB{

    public $db;

    public function __construct() {
        try {
            $this->db = new \Utils\Database(DB_TYPE, DB_HOST, DB_NAME, DB_USER, DB_PASS);
        } catch (\Exception $e) {
            die($e->getMessage());
        }
   }

}


każda klasa która dziedziczy po DB laczy sie z baza ponownie

class Klasa extends DB {

    public function CosTam() {
        return $this->db->select("SELECT * FROM costam");
    }
}