I have the following mysql query:

```
  SELECT order_id, CONCAT(firstname, ' ', lastname) AS customer, shipping_code, total, currency_code, currency_value, date_added, date_modified FROM oc_order` o LEFT JOIN (select komercijalista from oc_customer (order.customer_id = customer.customer_id))

```

I am trying to list values from `komercijalista` field (which belongs to `oc_customer` table) in `oc_order` table. I am trying to connect them by `customer_id` which both have, but I am failing at left join. Any suggestions, please? Apart from learning mysql better, which I am already trying to do and this is where I need your help. Thanx.