Estoy usando Codeigniter para crear una aplicación web y recibí este error:

Fatal error: Call to a member function result_array() on a 
non-object in /var/www/application/controllers/people.php on line 29

Esta es la clase people.php:

public function __construct()
{
    parent::__construct();
}

function People() {

}

function view($id) {
    echo "Hello world " . $id;
}

function all() {
    $this->load->model('people_model', '', TRUE);
    $allContacts = $this->people_model->get_all_contacts();
    $results = array();
    foreach ($allContacts->result_array() as $row) {
        $eachrow = array("personID"=>$row['personID'],"fName"=>$row['fName'],"lName"=>$row['lName'],"phoneNumber"=>"",
            "emailAddress"=>$row['emailAddress'],"address"=>$row['address'],"city"=>$row['city'],"state"=>$row['state'],"zip"=>$row['zip']);
        $results = push_array($results, $eachrow);
    }
    foreach ($results as $row) {
        $phoneData = $this->people_model->get_phone_by_id($row['personID']);
        $phoneNumbers = "";
        foreach ($phoneData->result_array() as $row2) {
            $phoneNumbers = $row2['type'] . " " . $row2['phoneNumber'] . " " . $row2['extension'];
        }
        $results['phoneNumber'] = $phoneNumbers;
    }

    $data['title']="Page Title Goes Here";
    $data['username']="Your Username";

    $this->load->view('header', $data);
    $this->load->view('people_results', $results);
    $this->load->view('footer');
}
}

Aquí está la clase people_model:

function __construct()
{
    // Call the Model constructor
    parent::__construct();
}

function get_all_contacts() {
    $query = $this->db->query('SELECT * FROM person');
    return $query->result();
}

function get_phone_by_id($id) {
    $query = $this->db->query('SELECT * FROM phoneNumber WHERE personID = '.$id);
    return $query->result();
}
}

Lo único que podría cuestionar en database.php es si el nombre de host necesita un número de puerto, pero no creo que haya ayudado cuando lo probé.

Acabo de intentar agregar (basado en una pregunta similar en la barra lateral)

$this->mydb = $this->load->database('realDB', TRUE);

al people_model y cambiando la db a mydb y recibí este error:

You have specified an invalid database connection group.

y esta es mi linea en database.php:

$db['default']['database'] = 'realDB';

Gracias por toda tu ayuda.