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<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
<?php
	//$username = $_POST["username"];
	$password = $_POST["password"];
	$con = mysqli_connect("", "root", "", "userdaten");
	$usernameabfrage = "SELECT password FROM daten WHERE username = '$_POST[username]'";

	$res = mysqli_query($con,$usernameabfrage);
	$erg = mysqli_fetch_array($res);
	$num = mysqli_num_rows($res);

	if($num > 1 || $num == NULL)
	{
		echo "Mehrfache User";
	}
	else
	{
		if($password == $erg["password"])
		{
			echo "Erfolgreich eingeloggt";
		}
		else
		{
			echo "Falsche Eingabe";
		}
	}

?>
</body></html>