How to return multiple rows with oracle function

There are three basic ways to return multiple rows by oracle function:
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A) use a refcursor as the return type
B) use an object table as the return type
C) use a mulit-delimited string as a return type (clob most likely)

A) use a refcursor as the return type
======================================

1.

CREATE OR REPLACE PACKAGE TYPES
AS
TYPE ref_c IS REF CURSOR;
END;

2.

CREATE OR REPLACE FUNCTION multiple_return
RETURN TYPES.ref_c
AS
l_cursor TYPES.ref_c;
BEGIN
OPEN l_cursor FOR
SELECT *
FROM emp;
RETURN l_cursor;
END;

3.

SELECT multiple_return
FROM DUAL




B)use an object table as the return type
==========================================

1.

CREATE OR REPLACE TYPE num_tab IS TABLE OF NUMBER;


2.

CREATE OR REPLACE PACKAGE pipeline
AS
FUNCTION get_num_row
RETURN num_tab PIPELINED;
END;


3.

CREATE OR REPLACE PACKAGE BODY pipeline
AS
FUNCTION get_num_row
RETURN num_tab PIPELINED
IS
BEGIN
FOR i IN 1 .. 20
LOOP
PIPE ROW (i);
END LOOP;

RETURN;
END get_num_row;
END;



4.

SELECT * FROM TABLE (pipeline.get_num_row);