Thanks Neophytos, but I made a mistake.
The actual result of the query writing procedure above is actually just the string:
product__new(NULL, :mfg_id, :name, :short_description, :long_description, :product_state, 'product', now(), null, null, null);
So the additional benefit of this method is that if the pg function changes, you may only have to change the call to the qd_add_* procedures.
