Object Association

// create customers object
$client = new client();
// client can have more then one address so create that object too
$contract = new contract();
// inner join the two tables on primary key and customerid
$client->inner_join($contract, 'id', 'client_id'); //left right and join are also possible
// get the result of the qeury
$this->view->client = $client->fetch_all(['limit'=>1])[0];

You loose all Activerecord functionality. Result is returned as \stdClass object

stdClass Object
(
    [id] => 1
    [initialen] => A.B.
    [achternaam] => Test
    [product] => Barebone Studio
    [orderdate] => 2026-08-22 10:33:19
    [begindate] => 2026-08-22 10:33:19
    [enddate] => 
    [client_id] => 6
)