Header location doesn't work in my wordpress plugin. - wordpress

Question

I'm writing an Wordpress plugin. With this plugin I update some data. The query and updating works fine, but my header("location: url"); doesn't work. If I place an echo, it won't give any error that the headers already send. It looks it doesn't do anything with those lines. My code...
<?php require_once('../../../wp-config.php');
$baanstatus_table=$wpdb->prefix . 'baanstatus';
$id = $_GET['id'];
$bijgewerkt =$_GET['bijgewerkt'];
$baanstatus= $_GET['baanstatus'];
$handicarts = $_GET['handicarts'];
$trolleys = $_GET['trolleys'];
$winterontheffing = $_GET['winterontheffing'];
$zomergreens = $_GET['zomergreens'];
$qualifying = $_GET['qualifying'];
$onderhoud_greens = $_GET['onderhoud_greens'];
$onderhoud_anders = $_GET['onderhoud_anders'];
$opmerkingen = $_GET['opmerkingen'];
global $wpdb;
$data_array =array('id' => $id,
'bijgewerkt' => $bijgewerkt,
'baanstatus' => $baanstatus,
'handicarts' => $handicarts,
'trolleys' => $trolleys,
'winterontheffing' =>$winterontheffing,
'zomergreens' =>$zomergreens,
'qualifying' =>$qualifying,
'onderhoud_greens' =>$onderhoud_greens,
'onderhoud_anders' =>$onderhoud_anders,
'opmerkingen' =>$opmerkingen
);
$where =array('id' => $id);
$wpdb->update( $baanstatus_table, $data_array, $where );
header("location:http://almeerderhout.fcklap.com/wp-admin/options-general.php?page=my-unique-identifier");
exit();
?>

Answer 1

Perhaps you should try the javascript, instead of PHP location.
<?php
echo '<script>location.href="http://almeerderhout.fcklap.com/wp-admin/options-general.php?page=my-unique-identifier";</script>';
?>

Answer 2

The below code will help you
<?php
wp_redirect( $location, $status );
exit;
?>
The above wordpress function will use to redirect Codex Link function reference

Answer 3

You should hook your plugin to a proper Wordpress action to avoid the "headers already sent error" when trying to redirect.
I found that a good place to perform redirects is the template_redirect action, so you can write something like this:
function do_something_then_redirect() {
// do something with $_GET or $_POST data
// then redirect to some url defined in the $redirect_url variable
wp_redirect($redirect_url);
die;
}
add_action('template_redirect', 'do_something_then_redirect');