Conditionals operation helps in php

I have this code, and want that if the value of $referal is 0 insert the value $referal2 ¿how do i can do?

if($referal > 0 && is_numeric($referal) && $site['refsys'] == 1 && $site['aff_click_req'] == 0){
                    $user = $db->QueryFetchArray("SELECT id FROM `users` WHERE `id`='".$referal."' LIMIT 1");
                    if($user['id'] > 0){
                        $addcash = $site['paysys'] == 1 ? ", `accountbalance`=`accountbalance`+'".$site['refcash']."'" : '';
                        $db->Query("UPDATE `users` SET `coin`=`coin`+'".$site['refcoins']."'".$addcash." WHERE `id`='".$user['id']."'");
                        $refpaid = 1;
                    }
                }
            }

$db->Query("UPDATE users SET ref='".$referal2."' WHERE email='".$email."'");

Regards and thanks.