Northwind db = new Northwind(Connections.ConnectionString);
db.Connection.Open();
Order_Detail orderDetail = db.Order_Details.Single(
o => o.OrderID == 10248
			&& o.ProductID == 42);

if (orderDetail.Quantity >= 10) {
	orderDetail.Discount = 0.05F;
}
using (db.Transaction = db.Connection.BeginTransaction())
{
	db.SubmitChanges(); db.Transaction.Commit();
}
