مشكل در اجراي كوئري

include("../functions/coect.php");
if(isset($_POST['submit'])){
$useame = $_POST['useame'];
$password = $_POST['password'];
$sql = "SELECT * FROM `tbl_users` WHERE useame= $useame AND password=$password";
$result=$coect->query($sql);
if($rows=$result->fetch(PDO::FETCH_ASSOC))
{
}