Oracle Landing __oracle on DBA

Recently met a lot of people to sysdba how to land annoyed, I provide a simple way of landing-with root logging to the UNIX system
bash-2.03$ su-oracle

bash-2.03$ Sqlplus
Sql*plus:release 9.2.0.1.0-production onðçæúëä3ôâ30 11:09:07 2006
Copyright (c) 1982, 2002, Oracle Corporation. All rights reserved.
Please enter user name: BMS
Please enter password:
Connect to:
Oracle9i Enterprise Edition Release 9.2.0.1.0-64bit Production
With the partitioning, OLAP and Oracle Data Mining options
Jserver Release 9.2.0.1.0-production
Sql>
Sql> Show User
USER is "BMS"
Sql> Conn/as SYSDBA
is connected
Sql> Show User
USER is "SYS"

This is already the SYS user, easy.

//There are certainly many ways to do this, such as
bash-2.03$ sqlplus "as Sysdba"
Sql*plus:release 9.2.0.1.0-production onðçæúëä3ôâ30 1 　　1:13:13 2006
Copyright (c) 1982, 2002, Oracle corporation.  All rights reserved.
Please enter a username:  BMS
Please enter password: 
Connect to:
oracle9i Enterprise Edition release 9.2.0.1.0-64bit production with the partitioning, OLAP and Oracle Data Mining options
Jserver release 9.2.0.1.0-production
sql> Show user
User is "SYS"
Sql>