Oracle在创建实例的时候，多数采用的是dbca的形式。。其实手动建库可以提供更大的*发挥的空间，根据情况进行定制

1. 登录Oracle用户
2. 指定SID（Instance Identifier）

    export ORACLE_SID=OCM

1. 确保必须的环境变量已经设置，大多数平台上 ORACLE_SID 和 ORACLE_HOME 必须设置

   export ORACLE_SID=OCM
   export ORACLE_HOME=/u01/app/oracle/product/11.2.0/dbhome_1

2. 选择 DBA 的认证方式

   1. 密码文件： password file
   2. 操作系统认证
3. 在 ORACLE_HOME/dbs 下创建静态参数文件（Initialization Parameter File）也就是initSID文件（Sample Initialization Parameter File）
   提前把init文件中的文件夹建好

    替换<ORACLE_BASE>
    db_name='ORCL'
    memory_target=1G
    processes = 150
    audit_file_dest='<ORACLE_BASE>/admin/orcl/adump'
    audit_trail ='db'
    db_block_size=8192
    db_domain=''
    db_recovery_file_dest='<ORACLE_BASE>/flash_recovery_area'
    db_recovery_file_dest_size=2G
    diagnostic_dest='/u01/app/oracle'
    dispatchers='(PROTOCOL=TCP) (SERVICE=ORCLXDB)'
    open_cursors=300 
    remote_login_passwordfile='EXCLUSIVE'
    undo_tablespace='UNDOTBS1'
    control_files = (ora_control1, ora_control2)
    compatible ='11.2.0'

1. 连上实例（Instance）

   1. 密码文件：

      $ sqlplus /nolog
      SQL> CONNECT SYS AS SYSDBA
      如果没有创建口令文件，随意数据密码均能连接

   2. 操作系统认证：

      $ sqlplus /nolog
      SQL> CONNECT / AS SYSDBA

2. 创建SPFILE

   SQL> CREATE SPFILE FROM PFILE;

3. 启动实例到NOMOUNT

   SQL> startup nomount;
   ORACLE instance started.

   Total System Global Area 1068937216 bytes
   Fixed Size 2235208 bytes
   Variable Size 616563896 bytes
   Database Buffers 444596224 bytes
   Redo Buffers 5541888 bytes

4. 执行创建数据库的语句（提前建好文件夹）

   替换密码sys_password
   替换UNDO表空间的名称
   CREATE DATABASE ORCL
   USER SYS IDENTIFIED BY sys_password
   USER SYSTEM IDENTIFIED BY system_password
   LOGFILE GROUP 1 ('/u01/app/oracle/oradata/orcl/redo01a.log','/u02/logs/orcl/redo01b.log') SIZE 100M BLOCKSIZE 512,

          GROUP 2 ('/u01/app/oracle/oradata/orcl/redo02a.log','/u02/logs/orcl/redo02b.log') SIZE 100M BLOCKSIZE 512,
          GROUP 3 ('/u01/app/oracle/oradata/orcl/redo03a.log','/u02/logs/orcl/redo03b.log') SIZE 100M BLOCKSIZE 512

   MAXLOGFILES 5
   MAXLOGMEMBERS 5
   MAXLOGHISTORY 1
   MAXDATAFILES 100
   CHARACTER SET AL32UTF8
   NATIONAL CHARACTER SET AL16UTF16
   --或者NATIONAL CHARACTER SET UTF8
   --选用NATIONAL CHARACTER SET AL32UTF8会报错
   EXTENT MANAGEMENT LOCAL
   DATAFILE '/u01/app/oracle/oradata/orcl/system01.dbf' SIZE 325M REUSE
   SYSAUX DATAFILE '/u01/app/oracle/oradata/orcl/sysaux01.dbf' SIZE 325M REUSE
   DEFAULT TABLESPACE users

     DATAFILE '/u01/app/oracle/oradata/orcl/users01.dbf'
     SIZE 500M REUSE AUTOEXTEND ON MAXSIZE UNLIMITED

   DEFAULT TEMPORARY TABLESPACE tempts1

     TEMPFILE '/u01/app/oracle/oradata/orcl/temp01.dbf'
     SIZE 20M REUSE

   UNDO TABLESPACE UNDOTBS1

     DATAFILE '/u01/app/oracle/oradata/orcl/undotbs01.dbf'
     SIZE 200M REUSE AUTOEXTEND ON MAXSIZE UNLIMITED;
   

5. 创建数据字典视图

   用 SYSDBA 权限执行
   @?/rdbms/admin/catalog.sql
   @?/rdbms/admin/catproc.sql
   @?/rdbms/admin/utlrp.sql
   用 SYSTEM 用户执行
   @?/sqlplus/admin/pupbld.sql

6. 至此数据库安装完毕

   查看数据库状态
   

   SQL> select open_mode from v$database;

   OPEN_MODE

   READ WRITE

   1 row selected.

   删除数据库
   

   SQL> startup nomount;
   ORACLE instance started.

   Total System Global Area 1068937216 bytes
   Fixed Size 2235208 bytes
   Variable Size 620758200 bytes
   Database Buffers 440401920 bytes
   Redo Buffers 5541888 bytes
   SQL> alter database mount exclusive;

   Database altered.

   SQL> alter system enable restricted session;

   System altered.

   SQL> drop database;

   Database dropped.

   Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
   With the Partitioning, OLAP, Data Mining and Real Application Testing options

通过DBCA创建数据库

1. 登录oracle用户

2. 输入 dbca 进行安装

       
       过程略
   

3. 打开闪回和归档。 闪回模式允许我们回到数据库的更早的时刻。

    sqlplus / as sysdba
    alter system set db_recovery_file_dest='/u01/app/oracle/flash_recovery_area' scope=spfile
    alter system set db_recovery_file_desc_size=2G
    SHUTDOWN IMMEDIATE;
    STARTUP MOUNT;
    ALTER DATABASE ARCHIVELOG;
    ALTER DATABASE FLASHBACK ON;
    ALTER DATABASE OPEN;

1. 检查设置

    sqlplus / as sysdba
    SELECT NAME, LOG_MODE, FLASHBACK_ON FROM V$DATABASE;

详细参考 oracle 官方文档 -> Oracle Database Administrator's Guide -> Creating and Configuring an Oracle Database -> Creating a Database with the CREATE DATABASE Statement