You don't have to be a DBA to get Oracle 10G set up for Liferay. If you just want to get something simple up and running quickly for your Ubuntu machine, just follow this guide:

[ This guide adapted from https://help.ubuntu.com/community/Oracle10g ]

Basics

Add this line to /etc/apt/sources.list file:

deb http://oss.oracle.com/debian unstable main non-free

As root, type:

apt-get update
apt-get install oracle-xe
/etc/init.d/oracle-xe configure

Edit your .bashrc file to include the lines:

ORACLE_HOME=/usr/lib/oracle/xe/app/oracle/product/10.2.0/server
PATH=$PATH:$ORACLE_HOME/bin
export ORACLE_HOME
export ORACLE_SID=XE

export PATH

Start a new bash shell for the changes to take effect.

To log in as a database administrator:

sqlplus sys as sysdba

It will then be possible for you to create and unlock user accounts using Oracle SQL commands - the details of which are beyond the scope of this doc.

Web GUI

Now for creating users / schema / ... you have a nice http interface to do it :

http://localhost:8080/apex/

Creating Liferay Tables

Liferay provides a dmp file that you can easily import using Oracle's "imp" command. Use "man imp" for more info.

The file is called: liferay-portal-sql-oracle-10-4.3.3.dmp

Here is the link to the download page:

liferay-portal-sql-oracle-10-4.3.3.dmp

Connecting

To see what you are connecting to, go to the /etc/oratab file. By default there is a line like so:

XE:/usr/lib/oracle/xe/app/oracle/product/10.2.0/server:Y

Basically, this is how you read it:

The three parts of that line tell the system that you have an instance/database called XE (your name might be different of course); it's ORACLE_HOME is /usr/lib/oracle/xe/app/oracle/product/10.2.0/server, so that's where the executables to run the database can be found; and right now it's IS to be automatically started or stopped.:Y

There you have it.

Configuring Tomcat

I'm not going to go into detail here since this is already documented, but just make sure you change the ROOT.xml in your tomcat config to point to this database schema, and also that you have the jar file of the oracle driver installed.

Good Luck!