> what I want is this
>
> CREATE VIEW V_TOPCUST
> AS
> select first 80000 *
> from customers
> order by weighted_value desc
>
> but it doesnt work.

How about this:

CREATE VIEW NEW_VIEW (
NAME,
WEIGHTED_VALUE)
AS
SELECT Name, Weighted_Value FROM Customers
WHERE Weighted_Value >=
(SELECT FIRST 1 SKIP 1 Weighted_Value FROM Customers
ORDER BY Weighted_Value DESC);

Cheers, Alex