<?php
$servername = "localhost";
$user = "*********";
$password ="*********";
$db = "fisherman";


$con = new mysqli($servername, $user, $password, $db);

if($con->connect_error) {
    die("ERROR <br>".$con->connect_error);
}

$name = $_GET['name'];
$password = $_GET['password'];

$res = $con->query ("SELECT ID FROM User WHERE Name = '"+$name+"'");

//This is the If-clause:
if ($res->num_rows != 0) {
    die ("Es existiert bereits ein Konto mit diesem Namen!" . $name);
}   else {
    echo "Der Name ist:" . $name;
}


$con->close();