Usually to create database we will use DBCA graphical user interface.

Some times may not have access to a graphical user interface then we can use the DBCA silent mode to create a database.

[oracle@rac2 ~]$ export ORACLE_HOME=/u01/app/oracle/product/11.2.0.4/db_1
[oracle@rac2 ~]$ export PATH=$ORACLE_HOME/bin:$PATH
[oracle@rac2 ~]$ which dbca
/u01/app/oracle/product/11.2.0.4/db_1/bin/dbca
[oracle@rac2 ~]$

[oracle@rac2 ~]$ mkdir -p /u01/app/oracle/oradata
[oracle@rac2 ~]$
-- No need to create folder POCNDEV, it will create automatically by dbca

[oracle@rac2 ~]$ dbca -silent -createDatabase -templateName General_Purpose.dbc -gdbName POCNDEV.rajasekhar.com -sid POCNDEV -sysPassword sys -systemPassword sys -emConfiguration NONE -datafileDestination /u01/app/oracle/oradata -storageType FS -characterSet AL32UTF8
Copying database files
1% complete
3% complete
35% complete
Creating and starting Oracle instance
37% complete
42% complete
47% complete
52% complete
53% complete
56% complete
58% complete
Registering database with Oracle Restart
64% complete
Completing Database Creation
68% complete
71% complete
75% complete
85% complete
96% complete
100% complete
Look at the log file "/u01/app/oracle/cfgtoollogs/dbca/POCNDEV/POCNDEV.log" for further details.
[oracle@rac2 ~]$

[oracle@rac2 ~]$ cat /etc/oratab | grep -i POCNDEV
POCNDEV:/u01/app/oracle/product/11.2.0.4/db_1:N         # line added by Agent
[oracle@rac2 ~]$

[oracle@rac2 ~]$ . oraenv
ORACLE_SID = [oracle] ? POCNDEV
The Oracle base remains unchanged with value /u01/app/oracle
[oracle@rac2 ~]$ sqlplus / as sysdba

SQL*Plus: Release 11.2.0.4.0 Production on Wed Dec 21 05:36:47 2016

Copyright (c) 1982, 2013, Oracle.  All rights reserved.


Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> select name, open_mode from v$database;

NAME      OPEN_MODE
--------- --------------------
POCNDEV   READ WRITE

SQL> archive log list
Database log mode              No Archive Mode <---
Automatic archival             Disabled
Archive destination            USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence     3
Current log sequence           5
SQL>
SQL> select file_name from dba_data_files;

FILE_NAME
--------------------------------------------------------------------------------
/u01/app/oracle/oradata/POCNDEV/users01.dbf
/u01/app/oracle/oradata/POCNDEV/undotbs01.dbf
/u01/app/oracle/oradata/POCNDEV/sysaux01.dbf
/u01/app/oracle/oradata/POCNDEV/system01.dbf

SQL> select name from v$tempfile;

NAME
--------------------------------------------------------------------------------
/u01/app/oracle/oradata/POCNDEV/temp01.dbf

SQL>

[oracle@rac2 ~]$ . oraenv
ORACLE_SID = [POCNDEV] ? +ASM
The Oracle base remains unchanged with value /u01/app/oracle
[oracle@rac2 ~]$ lsnrctl status LISTENER | grep -i POCNDEV
Service "POCNDEV.rajasekhar.com" has 1 instance(s).
  Instance "POCNDEV", status READY, has 1 handler(s) for this service...
Service "POCNDEVXDB.rajasekhar.com" has 1 instance(s).
  Instance "POCNDEV", status READY, has 1 handler(s) for this service...
[oracle@rac2 ~]$

TNS Entry Automatically will be added to TNSNAMES.ORA

POCNDEV =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = rac2.rajasekhar.com)(PORT = 1522))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = POCNDEV.rajasekhar.com)
    )
  )