How to install Oracle database express edition on Linux

The instructions in this blog post are validated to work on CentOS 6.4 version for installing Oracle 11g R2 database express edition. The same instructions should work OK on other Linux operating systems such as Red Hat Enterprise Linux and Oracle Enteprise Linux etc. This blog host also assumes that Oracle software is being installed for the first time on the Linux server. Change or skip some instructions if otherwise.

1) Open a new terminal

2) sudo su - root
3) mkdir /u01  (If it does not exist)
4) useradd oracle (If it does not exist)
5) groupadd dba (If the group dba does not exist)

6) usermod -g dba oracle

7) chown -R oracle:dba /u01

8) Edit /etc/oraInst.loc and add the below content.

inventory_loc=/var/opt/oracle/oraInventory
inst_group=dba

9) mkdir -p /var/opt/oracle/oraInventory

10) chown -R oracle:dba /var/opt/oracle/oraInventory

11) Install any missing Linux packages (RPMs) that are missing on the server.  The list of Linux version 6 packages required for installing 11g R2 are specified in the quick installation guide https://docs.oracle.com/cd/E11882_01/install.112/e24326.pdf

12) Download Oracle database express edition software from http://www.oracle.com/technetwork/database/database-technologies/express-edition/downloads/index.html for Linux.

13) The downloaded file name is oracle-xe-11.2.0-1.0.x86_64.rpm.zip

14) Login as root
15) unzip oracle-xe-11.2.0-1.0.x86_64.rpm.zip
16) cd Disk1
17) rpm -i oracle-xe-11.2.0-1.0.x86_64.rpm 
18) /etc/init.d/oracle-xe configure

19) ps -fu  oracle  (Verify the background processes are started for XE database instance)
20) sudo su  -  oracle  (Switch to oracle operating system user)
21) Edit /home/oracle/.bash_profile and add the below lines.

export ORACLE_HOME=/u01/app/oracle/product/11.2.0/xe
export PATH=$ORACLE_HOME/bin:$PATH
export ORACLE_SID=XE
export TNS_ADMIN=$ORACLE_HOME/network/admin

22) sqlplus ‘/ as sysdba’   (Login to the database with DBA privilege)
23) alter user hr account unlock;  (The sample HR schema is locked by default)
24) alter user hr identified by hr; (Reset the password of HR schema)

References: http://docs.oracle.com/cd/E17781_01/install.112/e18802/toc.htm#XEINL123