SQL Plus Options

If you want to change the SQL*Plus prompt, so that it automatically includes the name of the current instance, you will have to type the following commands in your SQL*Plus:

SQL> SET SQLPROMPT '_CONNECT_IDENTIFIER> '
home2> 
home2> 
home2> 

If you want to set the permanently then have it in glogin.sql on your client machine.

For example on my machine I set as below

D:\DevSuiteHome_1\sqlplus\admin\glogin.sql

SET SQLPROMPT 'SQL@ _CONNECT_IDENTIFIER> '

SET TIMING ON