Oracle SQL Developer is a free SQL development environment from Oracle. It provides a graphical tool to interact with your database. Furthermore, it is a complete standalone application thus neither SQL*Plus or Oracle Database Client software need to be installed beforehand in order to use it.

It does however, require that the Sun Java 6 JDK be installed on your system. Install it by typing:
sudo apt-get install sun-java6-jdk

To obtain the installable package, navigate to Oracle’s SQL Developer download page at:
http://www.oracle.com/technology/software/products/sql/index.html

Next we will convert the .rpm to a .deb to install it in Ubuntu. We’ll do this by using an application called ‘alien’. Install it by typing:
sudo apt-get install alien

Next, navigate to where you saved the SQL Developer .rpm package and type:
sudo alien -k –scripts sqldeveloper*.rpm

This will create a .deb package ready to be installed into our system. We do so by typing:
sudo dpkg -i sqldeveloper*.deb

Oracle SQL Developer is now installed. However, in order to run it, we need to point it to the JDK.

First we’ll create the missing directory by typing:
mkdir -p ~/.sqldeveloper

Next we’ll create an empty jdk file by typing:
touch ~/.sqldeveloper/jdk

Edit this file and input the path to the JDK by typing:
gedit ~/.sqldeveloper/jdk
and pasting into it:
/usr/lib/jvm/java-6-sun

Most valuable links:
http://samushka.blogspot.com/2009/04/installing-oracle-sql-developer-on.html