php中mysql参数化查询

$query = sprintf("SELECT * FROM Users where UserName='%s' and Password='%s'",mysql_real_escape_string($Username),mysql_real_escape_string($Password));
mysql_query($query);
或是  

$db = new mysqli("localhost", "user", "pass", "database");
$stmt = $mysqli -> prepare("SELECT priv FROM testUsers WHERE username=? AND password=?");
$stmt -> bind_param("ss", $user, $pass);
$stmt -> execute();