trigger_problem

I want to write a trigger as if I insert into table then the values get inserted into duplicate table instead of inserting table.
note : The value sould be inserted only into duplicate table not the real table.

I have the code plz modify it:

table name :  test
duplicate table name : test_dup

fields : id | name | pin

create or replace trigger a_trigger after insert on test for each row

begin

insert into test_dup values(:new.id,:new.name,:new.pin);

end;
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