我先在SQLPLUS上登陆为scott/tiger, 再执行CONNECT / AS SYSDBA，之后发现我可以查看SYS才能看到的东西，好象当前用户换成了SYS，我并没有用SYS密码，为什么？ 还有我怎么才能在SQLPLUS环境里查询当前登陆的用户名？

First of all, we need to get the Oracle 11g on our system. If you already have the file, you are good to skip this method and move to the installation part, but if ...