1) Go to ORACLE_HOME/sqlplus/admin.
2) Add this command to glogin.sql file. set sqlprompt '_USER>';
3) Connect to database.
############################ DEMO ############################
SQL> exit;
[oracle@demo]$ cd $ORACLE_HOME/sqlplus/admin
[oracle@demo]$ vi glogin.sql
set sqlprompt '_USER>';
[oracle@demo]$ sqlplus dbauser/password
SQL*Plus: Release 11.2.0.3.0 Production on Fri Aug 23 16:28:08 2013
Copyright (c) 1982, 2011, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
###################################################################
SQL PROMPT OPTIONS
_connect_identifier will display connection identifier.
_date will display date.
_editor will display editor name used by the EDIT command.
_o_version will display Oracle version.
_o_release will display Oracle release.
_privilege will display privilege such as SYSDBA, SYSOPER, SYSASM
_sqlplus_release will display SQL*PLUS release.
_user will display current user name.