private function getUsers( ){
    $users = $this->db->resource(dbMapper::USER);
 return $this->usersToArray( $users );}

 private function usersToArray( $users ){
        $result = array( );
        foreach ($users as $user){
            $result[] = array(
                'id'            => intval( $user->get('id') ),
                'name'          => $user->get('name')
            );
        }
        return $result;
    }

    public function getAllData( ){
        $result = array( );
        $result['users'] = $this->getUsers( );
        $results = print_r($result['users'], true); echo $results;
        return $result;
    }

$data = $model->getAllData( );
        $this->_helper->json( $data );

Array
(
    [0] => Array
        (
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    [1] => Array
        (
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    [2] => Array
        (
        )

    [3] => Array
        (
        )

    [4] => Array
        (
        )