[PDO] - Using bindParam() third parameter : data_type

Hi all, I am currently working on PDO. Exactly on the bindParam() function. The third parameter data_type seems to be here to force the type of the value ? But when I try : $sql = "INSERT INTO produit (idproduit, nom, marque)

        VALUES (NULL, :nom, :marque)";

$stmt = $dbh->prepare($sql); $nom = 'Testarossa'; $marque = 'Ferrari' ; $stmt->BindValue(':marque',$marque) ; $stmt->BindParam(':nom',$nom,PDO::PARAM_INT) ; $stmt->execute(); $nom = '250 GTO' ; $stmt->execute(); ?> I was expecting to have either a PHP error or an interger in my database. But in my DB I have : 22 Testarossa Ferrari 23 250 GTO Ferrari It mean that it didn't change if I have the third parameter or not. Or perhaps I miss something. Can someone tole me more ? Or just can someone told me where I can find information about it. Regards, Cyruss