--
-- ec_total_price/1
--
create or replace function ec_total_price(
  integer
) returns numeric as $$

DECLARE
	v_order_id	alias for $1;
        price           numeric;
BEGIN
	select into price
	    coalesce(sum(price_charged),0) - coalesce(sum(price_refunded),0)
            FROM ec_items
            WHERE order_id=v_order_id
            and item_state <> 'void';

	return price;

END;$$ language plpgsql;