สอบถามวิธีการ SELECT table โดยใช้ Where ค๊ะ

$user=$_session[user];
 $sql = "SELECT * FROM uploadworks WHERE `user` = '$user' ORDER BY id DESC ";

<?PHP
$user = $_GET['user'];
$sql = "SELECT * FROM uploadworks WHERE user = '$user' ORDER BY id DESC ";
$query = mysql_query($sql) or die(mysql_error());
?>

<?PHP
$user = $_POST['user'];
$sql = "SELECT * FROM uploadworks WHERE user = '$user' ORDER BY id DESC ";
$query = mysql_query($sql) or die(mysql_error());
?>