I am attempting to use jQuery DataTables AJAX ServerSide script...
I need to join the wp_usermeta table with the wp_users table...
How do I join the wp_usermeta table using the example server-side processing script? The script can be found at https://datatables.net/examples/server_side/simple.html
The relevant code is
$columns = array(
array( 'db' => 'user_login', 'dt' => 0 ),
array( 'db' => 'user_email', 'dt' => 1 ),
);