<?php
session_start();

//anzeigen

$dbc = mysqli_connect(
    "localhost",
    "root",
    "",
    "adressbuch"
)
or die("MYSQL: Conncection error \n" .mysqli_connect_error());

$username = $_POST ["user"];
$password = $_POST ["pw"];

$sql = "SELECT `Benutzername` FROM `accounts` WHERE `Benutzername` = '".$username."' AND `Passwort` = '".$password."'";
$result = mysqli_query($dbc, $sql);

if(mysqli_num_rows($result) > 0) {


    $_SESSION['session'] = true;
    header("Location: test.php");

}

?>