Manually Creating an Oracle Database on Windows
Below are the steps involved in manual database creation on Windows.
Steps in Database creation
Step 1: Decide on Your Instance Identifier (SID)
Step 2: Create the Initialization Parameter File
Step 3: Start the Instance.
Step 4: Issue the CREATE DATABASE Statement
Step 5: Create Additional Tablespaces
Step 6: Run Scripts to Build Data Dictionary Views

Step 1: Decide on Your Instance Identifier (SID)

Create a new service name using comment prompt
C:/>oradim -new –sid john –intpwd nive
(For help about oradim, type oradim/? In comment prompt)
Set the sid

Step 2: Create the Initialization Parameter File
Create init.ora file for your database
Or
Copy existing database init.ora parameter file and change the pathes in init.ora file

You should change the following parameters
db_name=jooo
instance_name=john (match with you already created sid)
log_archive_dest_1='LOCATION=D:\oracle\jooo\archive'
background_dump_dest=D:\oracle\jooo\bdump
core_dump_dest=D:\oracle\jooo\cdump user_dump_dest=D:\oracle\jooo\udump
control_files= ("D:\oracle\jooo\oradata\control01.ctl", "D:\oracle\jooo\oradata\control02.ctl", "D:\oracle\jooo\oradata\control03.ctl")

Step 3: Start the Instance.

In comment prompt
C:\>set ora_sid=john
C:\>sqlplus /nolog

Start an instance without mounting a database
Sql> startup nomount pfile=’location’

Step 4: Issue the CREATE DATABASE Statement

When you execute a CREATE DATABASE statement, Oracle performs (at least) the following operations.
* Creates the datafiles for the database
* Creates the control files for the database
* Creates the redo log files for the database and establishes the ARCHIVELOG mode
* Creates the SYSTEM tablespace and the SYSTEM rollback segment
* Creates the data dictionary
* Sets the character set that stores data in the database
* Sets the database time zone
* Mounts and opens the database for use

The general format follows:
CREATE DATABASE [database name]
[CONTROLFILE REUSE]
[LOGFILE [GROUP integer] file specification]
[MAXLOGFILES integer]
[MAXLOGMEMBERS integer]
[MAXLOGHISTORY integer]
[MAXDATAFILES integer]
[MAXINSTANCES integer]
[ARCHIVELOG|NOARCHIVELOG]
[CHARACTER SET charset]
[NATIONAL CHARACTER SET charset]
[DATAFILE filespec [autoextend]]
[DEFAULT TEMPORARY TABLESPACE tablespace filespec]
[UNDO TABLESPACE tablespace DATAFILE filespec]
[SET TIME_ZONE [time_zone_region]];

Example
CREATE DATABASE jooo
MAXINSTANCES 1
MAXLOGHISTORY 1
MAXLOGFILES 5
MAXLOGMEMBERS 5
MAXDATAFILES 100
DATAFILE
'd:\oracle\jooo\oradata\system01.dbf' SIZE 325M REUSE AUTOEXTEND ON NEXT 10240K MAXSIZE UNLIMITED
LOGFILE
GROUP 1 ('d:\oracle\jooo\oradata\redo01.log') SIZE 100M,
GROUP 2 ('d:\oracle\jooo\oradata\redo02.log') SIZE 100M
UNDO TABLESPACE "UNDOTBS1"
DATAFILE 'd:\oracle\jooo\oradata\undotbs01.dbf' SIZE 200M REUSE AUTOEXTEND ON NEXT 5120K MAXSIZE UNLIMITED
CHARACTER SET WE8MSWIN1252
NATIONAL CHARACTER SET AL16UTF16;

Step 5:
Create temprory tablespace and user tablespace.
Step 6: Run Scripts to Build Data Dictionary Views
Run the scripts necessary to build views, synonyms, and PL/SQL packages
@/vobs/oracle/rdbms/admin/catalog.sql
@/vobs/oracle/rdbms/admin/catproc.sql

Script Description

CATALOG.SQL
Creates the views of the data dictionary tables, the dynamic performance views, and public synonyms for many of the views. Grants PUBLIC access to the synonyms.

CATPROC.SQL R
It runs all scripts required for or used with PL/SQL.


OTHER OPTIONAL WORKS
* Specifying the Database Time Zone
* Specifying Passwords for Users SYS and SYSTEM
* CREATE DATABASE rbdb1
* USER SYS IDENTIFIED BY pz6r58
* USER SYSTEM IDENTIFIED BY y1tz5p
* Specifying FORCE LOGGING Mode
* Creating a Server Parameter File

Other important packages

catexp7.sql
Create v7 style export/import views against the v8 RDBMS

catblock.sql
create views of oracle locks.

catoctk.sql
Oracle Cryptographic ToolKit.

catobtk.sql
Contains scripts needed to use the PL/SQL Obfuscation Toolkit.

caths.sql
Create Heterogeneous Services data dictionary objects.

owminst.plb
create user ovm_sys for storing metadata. This will help in database export.

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