$host = "localhost"
    $user = 'usuario';
    $password = 'senha';
    $db = ' banco';

    $mysqli = new mysqli($host, $user, $password, $db);

    if (mysqli_connect_errno()) {
        print("Conexão falhou: %sn" . mysqli_connect_error());
        exit();

    }

Warning: mysqli::mysqli(): : Access denied for user 'usuario'@'localhost' to database ' banco' in /fakepath/arquivo.php on line 14
Conexão falhou: %s Access denied for user 'usuario'@'localhost' to database ' banco'