访问数据库的几种方法 - 数据库编程

这部分很基础，但是如果搞不清楚，对以后的学习会有影响。
SQL> select * from v$version where rownum=1;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production

1.sqlplus username/password@net_service_name （这是通过网络访问）
C:\Users\Administrator>sqlplus hr/hr@55

SQL*Plus: Release 11.2.0.1.0 Production on 星期日 5月 17 01:14:04 2015

Copyright (c) 1982, 2010, Oracle. All rights reserved.

连接到:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
======================================================== C:\Users\Administrator>sqlplus

SQL*Plus: Release 11.2.0.1.0 Production on 星期日 5月 17 01:16:47 2015

Copyright (c) 1982, 2010, Oracle. All rights reserved.

请输入用户名: hr@55
输入口令:

连接到:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> exit
从 Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
开
================================================================

C:\Users\Administrator>sqlplus /nolog

SQL*Plus: Release 11.2.0.1.0 Production on 星期日 5月 17 01:17:17 2015

Copyright (c) 1982, 2010, Oracle. All rights reserved.

SQL> conn hr/hr@55
已连接。

当然也可以过EZCONNECT连接数据库（easy connect）：

CONNECT username/password@host[:port]/service_name[/instance_name]
CONNECT username/password@[//]host[:port]/service_name

假如你连接没有成功检查一下客户端\network\admin\sqlnet.ora下：
SQL> select * from v$version where rownum=1;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production

添加EZCONNECT:
NAMES.DIRECTORY_PATH= (TNSNAMES,EZCONNECT)
下面模拟不添加EZCONNECT:
n罐?+?f?*?????? 3??FB8? 1?$郗忽n峨⒍??q?⑺l?e喝k?郗$>[??j堑?5喧??????v?醋?
??!低}?从帧?

n罐?+?f?*?????? 3??FB8? 1?$郗忽n峨⒍??q?⑺l?e喝k?郗$>[??j堑?5喧??????v?醋?
??!低}?从帧?

Oracle. All rights reserved.
连接到:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

3.
[oracle@localhost ~]$ sqlplus sys/manager as sysdba
SQL*Plus: Release 11.2.0.1.0 Production on 星期日 5月 17 02:12:49 2015
Copyright (c) 1982, 2009, Oracle. All rights reserved.
连接到:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

4.
[oracle@localhost ~]$ sqlplus
SQL*Plus: Release 11.2.0.1.0 Production on 星期日 5月 17 02:13:45 2015
Copyright (c) 1982, 2009, Oracle. All rights reserved.
请输入用户名: hr
输入口令:
连接到:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

5.
[oracle@localhost ~]$ sqlplus /nolog
SQL*Plus: Release 11.2.0.1.0 Production on 星期日 5月 17 02:15:09 2015
Copyright (c) 1982, 2009, Oracle. All rights reserved.
SQL> connect hr/hr
已连接。
SQL> exit
从 Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options 断开
[oracle@localhost ~]$ sqlplus /nolog
SQL*Plus: Release 11.2.0.1.0 Production on 星期日 5月 17 02:15:40 2015
Copyright (c) 1982, 2009, Oracle. All rights reserved.
SQL> connect sys/manager as sysd

访问数据库的几种方法(一)