създайте тригер в таблицата (преди актуализиране за всеки ред).
SQL> create table foo (hi varchar2(10), added_date date, modified_date date);
Table created.
SQL> create trigger foo_auifer
2 before update or insert on foo
3 for each row
4 declare
5 begin
6 if (inserting) then
7 :new.added_date := sysdate;
8 elsif (updating) then
9 :new.modified_date := sysdate;
10 end if;
11 end;
12 /
Trigger created.
SQL> insert into foo (hi) values ('TEST');
1 row created.
SQL> insert into foo (hi) values ('TEST2');
1 row created.
SQL> update foo set hi = 'MODDED' where rownum = 1;
1 row updated.
SQL> alter session set nls_date_format='dd-mon-yyyy hh24:mi:ss';
Session altered.
SQL> select * from foo;
HI ADDED_DATE MODIFIED_DATE
---------- -------------------- --------------------
MODDED 07-nov-2012 15:28:28 07-nov-2012 15:28:39
TEST2 07-nov-2012 15:28:30
SQL>