Can I use $_POST & $_GET at the same time?

Question

I have a following form:

Answer 1

Yes, however it should be:

$field1 = $_POST['field1'];
$field2 = $_POST['field2'];

$warehouse = $_GET['warehouse'];

$qry = "INSERT INTO table".$warehouse." ( field1, field2 ) VALUES ('".mysql_real_escape_string($field2)."', '".mysql_real_escape_string($field2)."')";
$result = @mysql_query($qry);

(Fixed syntax)