Anonymní profil petr – Programujte.com

Zdravim, muze mne nekdo poradit proc si mne v nasledujicim skriptu neulozi data do DB? Chyba neni zadna, do promennych se data ulozi ale do DB ne. 

 $servername = "localhost";
 $username = "root";
 $password = "";
 $dbname = "test";

$conn = new mysqli($servername, $username, $password,$dbname);

if ($conn->connect_error) {
    die("</br>"."Připojení k db se nezdařilo " . $conn->connect_error);
}
else {echo "</br>"."pripojeno k DB";}

if (empty($_POST['jmeno']) || empty($_POST['prijmeni']) || empty($_POST['email'])) {
exit;

}
$jmeno = trim($_POST['jmeno']);
$prijmeni = trim($_POST['prijmeni']);
$email = trim($_POST['email']);

$dotaz = "INSERT INTO db VALUES (?, ?, ?)"; 
$a = $conn -> prepare($dotaz); 
$a -> bind_param('sss',$jmeno,$prijmeni,$email); 
$a -> execute;

if (($a -> affected_rows) > 0 ){

echo "</br>"."zaznamy byly ulozeny do DB";
}
else echo "</br>"."neco se porouchalo";