9i servererror trigger

 oracle offers this trigger for oracle 9i to catch database errors.

<<Oracle 9i>>
  -------------
  connect system/<password>

  drop table log_errors_tab;

  create table log_errors_tab (
    id        NUMBER,
    log_date  DATE,
    log_usr   VARCHAR2(30),
    terminal  VARCHAR2(50),
    err_nr    NUMBER(10),
    err_msg   VARCHAR2(4000))
  tablespace tools;

  drop sequence log_errors_seq;

  create sequence log_errors_seq
    start with 1
    increment by 1
    minvalue 1
    nomaxvalue
    nocache
    nocycle;

  create or replace trigger log_errors_trig
  after servererror on database
  declare
    id number;
  begin
    select system.log_errors_seq.nextval into id from dual;

    FOR n IN 1..ora_server_error_depth LOOP
      insert into system.log_errors_tab values (id, sysdate, ora_login_user,