Keep history pl-sql changes

Question

I want to keep history of pl-sql changes
I have already found an example..
CREATE TABLE SOURCE_HIST -- Create history table
AS SELECT SYSDATE CHANGE_DATE, USER_SOURCE.*
FROM USER_SOURCE WHERE 1=2;
CREATE OR REPLACE TRIGGER change_hist -- Store code in hist table
AFTER CREATE ON SCOTT.SCHEMA -- Change SCOTT to your schema name
DECLARE
BEGIN
if DICTIONARY_OBJ_TYPE in ('PROCEDURE', 'FUNCTION',
'PACKAGE', 'PACKAGE BODY', 'TYPE') then
-- Store old code in SOURCE_HIST table
INSERT INTO SOURCE_HIST
SELECT sysdate, user_source.* FROM USER_SOURCE
WHERE TYPE = DICTIONARY_OBJ_TYPE
AND NAME = DICTIONARY_OBJ_NAME;
end if;
EXCEPTION
WHEN OTHERS THEN
raise_application_error(-20000, SQLERRM);
END;
show errors
but the select statement doesnt return any row
SELECT sysdate, user_source.* FROM USER_SOURCE
WHERE TYPE = DICTIONARY_OBJ_TYPE
AND NAME = DICTIONARY_OBJ_NAME;

Answer 1

Looks to me like the names were changed in 9i.
8i guide shows SYSEVENT,
LOGIN_USER, INSTANCE_NUM, DATABASE_NAME, DICTIONARY_OBJ_TYPE, DICTIONARY_OBJ_NAME, DICTIONARY_OBJ_OWNER
as available.
This PSOUG page shows variables ora_sysevent, ora_dict_obj_owner, ora_dict_obj_name being used.
The 9i App Dev Guide Ch 16 shows the new names.
So change DICTIONARY_OBJ_NAME to ORA_DICT_OBJ_NAME etc and you should be good to go. Shows you that you have to check information you find on Google!
HTH
Regards Nigel