SQL> select banner from v$version;

BANNER
----------------------------------------------------------------
Oracle Database 10g Release 10.1.0.2.0 - Production
PL/SQL Release 10.1.0.2.0 - Production
CORE    10.1.0.2.0      Production
TNS for 32-bit Windows: Version 10.1.0.2.0 - Production
NLSRTL Version 10.1.0.2.0 - Production

SQL> create table users (userid number, name varchar2(10), createdby number);

insert into users values (1, 'mike', 2);
insert into users values (2, 'admin', 0);
insert into users values (0, 'system', 0);
insert into users values (3, 'freddy', 2);
insert into users values (4, 'Naggie', 1);

userid          name           updatebyid         updatedbyname
------          ------         ------------       -------------
1               mike           2                  admin
2               admin          0                  system
3               freddy         2                  admin
.
.