CONNECT sys/manager AS SYSDBA;

CREATE OR REPLACE DIRECTORY dat_dir AS 'C:OradataData';
CREATE OR REPLACE DIRECTORY log_dir AS 'C:OradataLog';
CREATE OR REPLACE DIRECTORY bad_dir AS 'C:OradataBad';

GRANT READ ON DIRECTORY dat_dir TO scott;
GRANT WRITE ON DIRECTORY log_dir TO scott;
GRANT WRITE ON DIRECTORY bad_dir TO scott;

external table:

CREATE TABLE address (id      number,
                     house_num     varchar2(20),
                     rcl_id     NUMBER,
                     rna_id     NUMBER,
                     xmin     NUMBER,
                     ymin     NUMBER
                     )
 ORGANIZATION EXTERNAL
 (
   TYPE ORACLE_LOADER
   DEFAULT DIRECTORY dat_dir
   ACCESS PARAMETERS
   (
     records delimited by newline
     badfile bad_dir:'address%a_%p.bad'
     logfile log_dir:'address%a_%p.log'
     fields terminated by ','
     missing field values are null
     ( id,
       house_num,
       rcl_id,
       rna_id,
       xmin,
       ymin
     )
   )
   LOCATION ('address.dat')
 )
 PARALLEL 4
 REJECT LIMIT UNLIMITED;

-----------------
Then you can use the Merge command to insert or update your production table.

MERGE INTO revenue dest
USING (SELECT id,
                      house_num,
                      rcl_id,
                      rna_id,
                      xmin,
                      ymin
               FROM address) src
ON (dest.id = src.id)
WHEN MATCHED THEN
  UPDATE SET dest.house_num = src.house_num,
                      dest.rcl_id=src.rcl_id,
                      dest.rna_id=src.rna_id,
                      dest.xmin=src.xmin,
                      dest.ymin=src.ymin  
WHEN NOT MATCHED THEN
  INSERT (id, house_num, rcl_id,rna_id,xmin,ymin)
  VALUES (src.id, src.house_num, src.rcl_id,src.rna_id,src.xmin,src.ymin);

External tables are not avaiable in 8i.
the one workaroudn without using UTL_FILE or sql*loader is to use of OCI or perl.

90% of opensource users / developers find PERL to be the best text processing language.
you have to write a perl wrapper to parse the text file, strip the data and load into the oracle.
performance is "ok" in many cases ( we use it for BIOINFORMATICS). advantage is , with perl code, you can do any kind of processing with are not possible with sql*loader~