Return two lists in PLSQL - oracle

Question

I am trying to return a list of 3 VARRAYS/COLLECTIONS to my application. I am having trouble though, think I am either implementing the solution incorrectly
create or replace
PROCEDURE "GENERATE_PEOPLE"
(
-- In this example pi_string will be "This.is.a.test"
pi_string IN VARCHAR2 ,
po_firstnames OUT VARRAY ,
po_lastnames OUT VARRAY ,
po_descriptions OUT VARRAY ,
po_error_code OUT VARCHAR2 ,
po_error_message OUT VARCHAR2
)
IS
CURSOR people_cursor IS SELECT firstname, lastname, description FROM people;
BEGIN
FOR person_rec IN people_cursor
LOOP
-- This is where I am trying to return 3 collections of po_firstnames, po_lastnames, po_descriptions
-- The print statements below print out exactly what it is I am trying to return!
dbms_output.put_line('Firstname: ' || person_rec.firstname);
dbms_output.put_line('Lastname: ' || person_rec.lastname);
dbms_output.put_line('Description: ' || pi_string || person_rec.description);
-- This is where the values would be added to the list/array/collection
po_firstnames(num?) := person_rec.firstname;
po_lastnames(num?) := person_rec.lastname;
po_descriptions(num?) := pi_string || person_rec.description;
END LOOP;
RETURN;
END;
Any help is greatly appreciated
Oracle 10g
And I am calling it as such:
DECLARE
TYPE po_firstnames AS vc2_array;
TYPE po_lastnames AS vc2_array;
TYPE po_descriptions AS vc2_array;
po_error_code VARCHAR2(50);
po_error_message VARCHAR2(50);
BEGIN
GENERATE_PEOPLE
(
'This.is.a.test' ,
po_firstnames ,
po_lastnames ,
po_descriptions ,
po_error_code ,
po_error_message
);
END;

Answer 1

VARRAY cannot be used directly as the type of a parameter or variable. Instead you need to create a TYPE that is a VARRAY like this (e.g.):
create type vc2_array as varray(100) of varchar2(4000);
then:
create or replace
PROCEDURE "GENERATE_PEOPLE"
(
-- In this example pi_string will be "This.is.a.test"
pi_string IN VARCHAR2 ,
po_firstnames OUT vc2_array ,
po_lastnames OUT vc2_array ,
po_descriptions OUT vc2_array ,
po_error_code OUT VARCHAR2 ,
po_error_message OUT VARCHAR2
)
Generally I would use TABLE rather than VARRAY, bacause with TABLE you do not have to specify a maximum number of elements:
create type vc2_array as table of varchar2(4000);
The values can then be assigned like this in your loop:
num := num+1; -- num must be declared above and initialised to 0
po_firstnames(num) := person_rec.firstname;
po_lastnames(num) := person_rec.lastname;
po_descriptions(num) := pi_string || person_rec.description;
However it would be more efficient to do this:
create or replace
PROCEDURE "GENERATE_PEOPLE"
(
-- In this example pi_string will be "This.is.a.test"
pi_string IN VARCHAR2 ,
po_firstnames OUT vc2_array ,
po_lastnames OUT vc2_array ,
po_descriptions OUT vc2_array ,
po_error_code OUT VARCHAR2 ,
po_error_message OUT VARCHAR2
)
IS
BEGIN
SELECT firstname, lastname, pi_string||description
BULK COLLECT INTO po_firstnames, po_lastnames, po_descriptions
FROM people;
END;