Oracle PL/SQL Version Controlling

--Firstly, create a table to store change history

CREATE TABLE DBChangeHistory AS 
SELECT SYSDATE CHANGE_DATE, ALL_SOURCE.*
FROM   ALL_SOURCE 
WHERE 1=2;

--Secondly, create a trigger to store the code when it's changed
--You can modify this code to store Version number
CREATE OR REPLACE TRIGGER tgTrackDBChange
AFTER CREATE ON SCOTT.SCHEMA
DECLARE
BEGIN
  IF ORA_DICT_OBJ_TYPE in ('PROCEDURE', 'FUNCTION',
                           'PACKAGE',   'PACKAGE BODY',
                           'TYPE',      'TYPE BODY')
  THEN     
     INSERT INTO DBChangeHistory
     SELECT sysdate, all_source.* 
  FROM ALL_SOURCE
     WHERE  TYPE = ORA_DICT_OBJ_TYPE
  AND  NAME = ORA_DICT_OBJ_NAME;
  END IF;
EXCEPTION
  WHEN OTHERS THEN
       --Raise error here;
END;