前两天在ITPUB上看到一个帖子，提到如何用最快的方法以SYSDBA登陆数据库。
有人给出的方法是sqlplus直接回车，然后在提示用户名时输入/ as sysdba：
[oracle@yans1 ~]$ sqlplus
SQL*Plus: Release10.2.0.3.0 - Production on星期六8月8 22:01:47 2009
Copyright (c) 1982, 2006, Oracle. All Rights Reserved.
Enter user-name: / as sysdba
Connected to:
Oracle Database10gEnterprise Edition Release10.2.0.3.0 - 64bit Production
With the Partitioning, OLAP and Data Mining options
SQL>
其实在10g中，sqlplus做了改进，可以在sqlplus后面直接加上/ as sysdba，而不需要双引号或单引号：
[oracle@yans1 ~]$ sqlplus / as sysdba
SQL*Plus: Release10.2.0.3.0 - Production on星期六8月8 22:05:14 2009
Copyright (c) 1982, 2006, Oracle. All Rights Reserved.
Connected to:
Oracle Database10gEnterprise Edition Release10.2.0.3.0 - 64bit Production
With the Partitioning, OLAP and Data Mining options
SQL>
在9i中，sqlplus还没有这个功能，必须在/ as sysdba两边加上引号。
bash-2.03$ sqlplus / as sysdba
Usage: SQLPLUS [ [<option>] [<logon>] [<start>] ]
where <option> ::= -H | -V | [ [-L] [-M <o>] [-R <n>] [-S] ]
本文URL地址：http://www.bianceng.cn/database/Oracle/201410/45455.htm
<logon> ::= <username>[/<password>][@<connect_string>] | / | /NOLOG
<start> ::= @<URI>|<filename>[.<ext>] [<parameter> ...]
"-H" displays the SQL*Plus version banner and usage syntax
"-V" displays the SQL*Plus version banner
"-L" attempts log on just once
"-M <o>" uses HTML markup options <o>
"-R <n>" uses restricted mode <n>
"-S" uses silent mode
bash-2.03$ sqlplus "/ as sysdba"
SQL*Plus: Release9.2.0.4.0 - Production on星期六8月8 22:25:16 2009
Copyright (c) 1982, 2002, Oracle Corporation. All rights reserved.
Connected to:
Oracle9i Enterprise Edition Release9.2.0.4.0 - 64bit Production
With the Partitioning, OLAP and Oracle Data Mining options
JServer Release 9.2.0.4.0 - Production
SQL>
从这种小的变化也可以看出，对于Oracle最基础的sqlplus工具而言，也在不断的提高易用性。