Master Detail InsertCommand

Hi,

I am developing an application that accesses a Foxpro database (.dbf
files) with two tables, the master table (customers) has a field (id)
which is primary key. The detail table (orders) has a primary key
formed by the fields: customerid, orderid. The order id is a not
automatic counter for every customer orders.

Ex:

CustomerID 1 - OrderID 1
CustomerID 1 - OrderID 2
CustomerID 2 - OrderID 1
CustomerID 2 - OrderID 1
CustomerID 2 - OrderID 2

I don't know how to build the InsertCommand for the Orders table. Those
are the problems I have:

- To know the order id I need to query the database before inserting.
Can I make an InsertCommand with two commands? The first queries the
database for orderid and the second inserts the record.
- I can not make a single query because I think Foxpro does not allow
sentences like this:
INSERT INTO orders (customerid, orderid) VALUES (1, SELECT
max(orderid)+1 WHERE customerid=1)

I suppose if I don't relay on InsertCommand and handle the insertions
myself I will have more control but I wanted to take advantage of
ado.net automatic updates with insertcommand.

Thank you very much!