PHP - Sumar columnas con PHP de base de datos

$servername = "localhost";

$database = "base";

$username = "usuario";

$password = "pass;

// Create connection

$link = mysqli_connect($servername, $username, $password, $database);

// Check connection

if (!$link) {

    die("Connection failed: " . mysqli_connect_error());

}

echo "Connected successfully";

echo $id;

$consulta = mysqli_query("SELECT * FROM preguntas WHERE idv = `$id` AND status = `Pregunta`");

$total = 0;

while($row = mysqli_fetch_array($link, $consulta))

{

    $total = $total + $row['valor'];

}