code.php?user=p1&x=10&y=1

    $id1 = $HTTP_GET_VARS["id1"];
    $x = $HTTP_GET_VARS["x"];
    $y = $HTTP_GET_VARS["y"];
    $qry = mysql_query("UPDATE ".$dbTable." SET x=".$x.", y=".$y." WHERE id=".id1."");

>returns "Parse error: syntax error, unexpected T_STRING in \...\code.php on line 26"

What's wrong?

$id1 = isset($_GET['id1']) ? $_GET['id1'] : '';
$x = isset($_GET['x']) ? $_GET['x'] : '';
$y = isset($_GET['y']) ? $_GET['y'] : '';

$dbh = new PDO('mysql:host=localhost;dbname=shitdb', '>>1', 'faggot');
$s = $dbh->prepare("UPDATE ? SET x = ?, y = ? WHERE id1 = ?");
$s->execute(array($dbTable, $x, $y, $id1));