how to return multiple row from oracle 9i procedure

Hi Friends,
I have an oracle procedure/function which will return set of rows. Rows fetched from table will be changed in the procedure and then returned . Is there any I could return a ref cursor after first manipulating the records.
I newbie to pl/sql please help
Sonu
[ May 23, 2003: Message edited by: Sonu Ghosh ]

Dear Friends,
This is how I am trying to do this task.
Retrieving records into cursor. Running a loop and fetching single record from cursor at a time .After changing the record I am putting that in collection(Nested Table). Returning the collection from stored procedure.
Problem in this way is Oracle is keeping Nested Table in memory till connection is close not when statement is close. As I am using connection pool I am not sure when actually that connection will be closed .
Is there any other efficient way to do this task.
Thanks in adv .
Sandeep