Help with learning Triggers

Question

Hello,
I'm afraid this is a very basic question from someone just learning Oracle.
I have downloaded 10g onto my work Windows XP laptop.
When trying to create a trigger through sql*plus, I keep getting 'trigger created with compilation errors'
When going to EM, I keep getting :
"SQL Error
Failed to commit: ORA-04072: invalid trigger type"
This happens with any combination of before/after update,insert,delete - and it's stumping me. i was just working my through an easy example in a book.
here's the trigger body from the EM:
after insert or update on integers #no matter what combination i use , i get the same
for each row
begin
end;
That error:
Oracle Error :: ORA-04072
Specify either INSERT, UPDATE or DELETE.
Am i making some obvious typo that i just can't see????
Thanks for any help, it's appreciated....

Answer 1

it's just the most basic learning example.........
the table........
SQL> select * from integers;
C1 C2
1 odd
2 even
3 odd
4 even
5 odd
7 odd
7 even
7 rows selected.
and as for the trigger, as i posted above, i took out everythinng from the body eventually as i tried every combination of before/after insert/update/delete and still kept getting the same error (with or wihtout anything in the body).
trigger:
create or replace trigger tg
after insert or update on integers
for each row
begin
end;
thanks!