How to select rows where column value IS NOT NULL using CodeIgniter’s ActiveRecord?

I’m using CodeIgniter’s Active Record class to query the MySQL database. I need to select the rows in a table where a field is not set to NULL:

$this->db->where('archived !=', 'NULL');
$q = $this->db->get('projects');

That only returns this query:

SELECT * FROM projects WHERE archived != 'NULL';

The archived field is a DATE field.

Is there a better way to solve this? I know I can just write the query myself, but I want to stick with the Active Record throughout my code.

Answer

where('archived IS NOT NULL', null, false)