Create the PTF implementation package replicate_p.

CREATE PACKAGE replicate_p 
AS 
    FUNCTION describe(tab IN OUT DBMS_TF.TABLE_T, 
                      replication_factor NATURAL) 
        RETURN DBMS_TF.describe_t; 
     
    PROCEDURE fetch_rows(replication_factor NATURALN); 
 
END replicate_p; 

Create the PTF implementation package body replicate_p.

CREATE PACKAGE body replicate_p 
AS  
    FUNCTION describe(tab IN OUT DBMS_TF.Table_t 
                     , replication_factor NATURAL) 
        RETURN DBMS_TF.describe_t AS 
    BEGIN 
        RETURN DBMS_TF.describe_t(row_replication => True); 
    END; 
     
    PROCEDURE fetch_rows(replication_factor NATURALN) 
    AS 
    BEGIN 
        DBMS_TF.ROW_REPLICATION(replication_factor); 
    END; 
END replicate_p; 

Create a standalone PTF named replicate.

CREATE FUNCTION replicate(tab TABLE,  
                          replication_factor NATURAL) 
RETURN TABLE PIPELINED ROW POLYMORPHIC USING replicate_p; 

This example sets the replication_factor to 2 which results in doubling the number of rows.

SELECT *  
FROM replicate(scott.dept, replication_factor => 2)

Invoke the PTF replicate in a query.

SELECT *  
FROM replicate(scott.dept, replication_factor => 0)

SELECT deptno, COUNT(*)  
FROM replicate(scott.emp, 1e6)  
GROUP BY deptno

SELECT COUNT(*)  
FROM replicate(dual, 1e9)