PHP: session isn't saving before header redirect

Question

I have read through the php manual for this problem and it seems quite a common issue but i have yet to find a solution. I am saving sessions in a database. My code is as f

Answer 1

You should start the session before using the session array.

PHP Code,
session_start();
$_SESSION['userID'] = $user->id;

header('Location: /subdirectory/index.php');