[Deprecated] DMZ 1.5.4 (DataMapper OverZealous Edition)

[eluser]OES[/eluser]
Is this type of Query possible with DMZ ?

Code:

SELECT
    orders.*,
    COALESCE(overs, 0) AS some_total
FROM orders
LEFT JOIN
    (
    SELECT order_id, SUM(overs) AS overs
     FROM extras
     ) o
    ON  orders.id = o.order_id
WHERE orders.user_id = xx

If so how would you go about it.

Orders have a relationship with extras