In these days lots of people are talking about RAILS 3, the biggest and most happening version as compared with the previous ones. There are many changes in each and every part of the application.
Here, we will cover the changes, dependencies, how we install rails 3 on windows and linux and a basic sample RAILS 3 application..
So Here we go:
1st We will install rails 3 on windows.
Note: To Install rails 3, you must be having ruby-1.8.7 or higher, So If you’re running with ruby-1.8.6, it’s time to upgrade now.
To do that download the executable version of ruby(either 1.8.7 or 1.9.1) click here and download Ruby 1.9.1-p378 (RC2). Once done run the setup and check both the option as per the below image.

Once done with the installation, You need to copy 3 DLL files under /Ruby19/bin folder and these files are:
1. readline.dll (Download from here)
2. ssleay32.dll (Download from here)
3. zlib.dll (Download from here)
4. OpenSSL(Download from Here)
For better examples, you can also refer UKNatureBlog
Once you copied all the dependencies, now it’s time to start few gems, which will help us to install rails 3.0.
Do update your system with this:
gem update –system
Because bundler and i18n looks for rubygem >= 1.3.6
To install these gems, open up command prompt and type:
gem install tzinfo builder memcache-client rack rack-test rack-mount erubis mail text-format thor bundler i18n
and you’ll find progress something like this:

You have to install rack as well in order to install rails 3. To do that type:
gem install rack
Once done with it, now its time to install rails 3.0, so do this:
gem install rails –pre
Note: Don’t worry if your installation fails somewhere in the middle. Important is your gems(like activerecord, activeresource etc.) should be installed successfully, no matter ri and rdoc encounters an error.
So far we’ve installed ruby-1.9 and rails-3.0. Now it’s time to create your first rails application. Here I am assuming that you already have mysql installed in your system. So open up your command prompt and fire this command.
rails myrails3_app -J -d mysql
and you’ll see progress like this:

Other possible parameters:
1. –skip-activerecord
Now let’s look at the directory structure which rails-3.0 has created for us:

At first glance you will notice that, there is no change in the directory structure, everything is the same (except for two files config.ru and Gemfile).
We will create a sample RAILS 3 Application in our next tutorial soon.