Using multiple databases with helper files

[eluser]JoostV[/eluser]
Once again, it is very bad practise to put data handling in your helpers. Google why.

But, as a theoretical discussion, you simply pass the $db object as a parameter.
controller:

Code:

$db1 = $this->load->database('group_one', TRUE);
$result = some_function($db1);

helper:

Code:

function some_function($db){
    $query = $db->get('some_table');
    return $query->num_rows() > 0 ? $query->result_array() : array();
}