MongoDB shell, learn directly in browser
Anatoly Mironov
Are you also curious about NoSQL databases. Well, MongoDB is one of the most known ones. MongoDB has a javascript syntax (json), I like it. Try out the interactive shell at the mongodb site. 
Quickstart on Ubuntu
To test it on Ubuntu, just install an existing apt-package:
sudo apt-get install mongodbCreate the default folder and change permissions:
sudo mkdir -p /data/db/
sudo chown `id -u` /data/dbThen jump directly into mongo db shell:
mongoHere are some useful and self explaining commands:
show dbs
show collections
show users
use <db-name>