Anyone who used PLSQL is already familiar with the NVL(foo, bar) function..
This feature lets us set a default value if the first is null.
But if you want something like that in Ruby and Java? :>
Bootstrap project contains all configuration needed to start this blog tutorials.
You just need to clone this project, run bundle install and start following the tutorials:
git clone https://github.com/fpastore/bootstrap.git
Because there are already excellent tutorials available, I will not show how to configure this bootstrap application, but I will leave the tutorials that inspired me to use this tools.