ORA-04079: invalid trigger specification — row level trigger

Question

I am trying to create a trigger to notify when an employee's name is changed.

 create or replace trigger name_change
 after update on employee_table
 for each row when (old.e_name != new.e_name);
 begin
 dbms_output.putline(:old.e_name || 'changed their name to' || :new.e_name);
 end;

Not sure where the error is coming from.

Answer 1

when (old.e_name != new.e_name)之后应该没有分号