$dbc = mysqli_connect('localhost', 'root', '', 'BazaPodataka') or die('Error.');



$sql="SELECT username, password  FROM users WHERE username=? AND password=?;";


 $stmt=mysqli_stmt_init($dbc);

 if (mysqli_stmt_prepare($stmt, $sql)){

mysqli_stmt_bind_param($stmt,'ss',$username,$password);
mysqli_stmt_execute($stmt);
mysqli_stmt_store_result($stmt);
 }

mysqli_stmt_bind_result($stmt, $a, $b);

mysqli_stmt_fetch($stmt);
if (mysqli_stmt_num_rows($stmt)>0) echo ('Uspjesan login');
else echo "Nema takvog klijenta ".$password;