[root@blliu ~]# su - oracle
[oracle@blliu ~]$ cd $ORACLE_HOME/dbs
[oracle@blliu dbs]$ touch initorcl.ora
[oracle@blliu dbs]$ vi initorcl.ora                  //加入db_name=orcl
[oracle@blliu dbs]$ export ORACLE_SID=orcl
[oracle@blliu dbs]$ sqlplus / as sysdba

SQL*Plus: Release 10.2.0.4.0 - Production on Mon Jan 25 19:03:23 2010

Copyright (c) 1982, 2007, Oracle.  All Rights Reserved.

Connected to an idle instance.

SQL> startup nomount
ORACLE instance started.

Total System Global Area  171966464 bytes
Fixed Size                  2082496 bytes
Variable Size             113248576 bytes
Database Buffers           50331648 bytes
Redo Buffers                6303744 bytes
SQL> create database orcl
  2  datafile
  3  '/u01/app/oracle/orcl/system01.dbf' size 300m autoextend on next 10m
  4  sysaux datafile
  5  '/u01/app/oracle/orcl/sysaux01.dbf' size 300m autoextend on next 10m
  6  logfile
  7  group 1 ('/u01/app/oracle/orcl/redo101.log') size 10m,
  8  group 2 ('/u01/app/oracle/orcl/redo201.log') size 10m
  9  character set zhs16gbk;

Database created.

SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup
ORACLE instance started.

Total System Global Area  171966464 bytes
Fixed Size                  2082496 bytes
Variable Size             113248576 bytes
Database Buffers           50331648 bytes
Redo Buffers                6303744 bytes
Database mounted.
Database opened.
SQL> @?/rdbms/admin/catalog.sql    //创建数据库的基表，视图，同义词等

PL/SQL procedure successfully completed.

SQL> @?/rdbms/admin/catproc.sql   //创建数据库的程序包，过程，函数，同义词等

PL/SQL procedure successfully completed.

SQL>
SQL> SET SERVEROUTPUT OFF
SQL> connect system/manager
Connected.
SQL> @?/sqlplus/admin/pupbld.sql    //创建使用SQLPLUS工具连接所需的视图，同义词等
SQL>
SQL> -- End of pupbld.sql
SQL> exit    
Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
[oracle@blliu dbs]$ sqlplus / as sysdba

SQL*Plus: Release 10.2.0.4.0 - Production on Mon Jan 25 19:24:00 2010

Copyright (c) 1982, 2007, Oracle.  All Rights Reserved.

Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> create table test (id number);

Table created.

SQL> insert into test values (1);

1 row created.

SQL> commit;

Commit complete.

至此，一个最简单的Oracle数据库就创建成功了，我们可以在此基础上创建undo tablespace,temporary tablespace,安装其他组建使其变得更加完整。