Installing PostgreSQL 9.1 on Ubuntu 11.04

first install python-software-properties:
sudo apt-get install python-software-properties

now add repository and update apt.
sudo add-apt-repository ppa:pitti/postgresql
sudo apt-get update

now instal postgresql
sudo apt-get install postgresql-9.1 libpq-dev

Now change the postgres user password (still running as root):
su postgres
psql -d postgres -U postgres
alter user postgres with password 'a';
\q

To install GUI client pgsql
sudo apt-get install pgadmin3

Install Ubuntu Desktop on Ubuntu server 11.04

First you nee to make sure you have enabled Universe and multiverse repositories in /etc/apt/sources.list file once you have enable you need to use the following command to install GUI

sudo apt-get update

sudo apt-get install ubuntu-desktop

The above command will install GNOME desktop

If you wan to install a graphical desktop manager without some of the desktop addons like Evolution and OpenOffice, but continue to use the server flavor kernel use the following command

sudo apt-get install --no-install-recommends ubuntu-desktop

If you want to install light weight desktop install xfce using the following command

sudo apt-get install xubuntu-desktop

If you want to install KDE desktop use the following command

sudo apt-get install kubuntu-desktop

Install Sun java 6 jre/jdk from PPA in Ubuntu 11.04

Sun Java packages for Ubuntu 11.04 Natty has not yet available in the official repository. However, there’s an easy way to get sun-java-jre, sun-java-jdk, and sun-java-jre-plugin by adding a third-party ppa.

Open up a terminal window under Application -> Accessories -> Terminal, adding the ppa by:

sudo add-apt-repository ppa:ferramroberto/java
sudo apt-get update

Then, install java jre:

sudo apt-get install sun-java6-jre sun-java6-jre-plugin


Install Jdk by the command:

sudo apt-get install sun-java6-jdk

Now check java version

java -version