Function Hangs

I created the following function below. It hangs when I need to do the
table update. Originally I wrote this function in MS SQL using cursors.
However reading the documentation, I couldn't figure out how to loop
through a cursor so I tried the FOR...LOOP instead.

Any help would be appreciated.
TIA

CREATE FUNCTION "removeduppchange"() RETURNS "int4" AS '

DECLARE
v_prevProd int4;
v_count int4;
myRec RECORD;

BEGIN
v_prevProd := 0;
v_count :=0;
FOR myRec IN
-- Find all duplicate records that are still valid according to date
Select o.keyf_products ,o.keyp_priceschedule
from ozpricing o,
(
Select keyf_products from ozpricing
group by keyf_products
having count(*) >1
) a
where o.keyf_products =a.keyf_products
and o.keyf_products =76
and (date_end >= ''now'' and date_start <= ''now'')
order by keyf_products,date_start desc LOOP

--If we find that the previous keyF matches the current keyF then lets
mark it.
if myRec.keyf_products = v_prevProd then
begin
/*
PROBLEM HAPPENS HERE. If I remove update statement, I get the correct
record
count of how many records should be marked

*/
update ozpricing set useascurrprice = 0 where
keyp_priceschedule = myRec.keyp_priceschedule;
v_count = v_count + 1;
end;
end if;
v_prevProd := myRec.keyf_products;
END LOOP;
RETURN v_count;
END; ' LANGUAGE 'plpgsql';

Patrick Hatcher
Macys.Com
Legacy Integration Developer
415-932-0610 office