I push the source code of this blog both on GitHub and to my EC2 instance, where it runs.

The file config/database.yml stores sensible informations like database’s passwords, and I didn’t want to push it on GitHub.
After a quick search on stackoverflow I didn’t find any answer to my problem, but then I solved it.
I don’t know if it is the best way, but this is what I did.

Since I don’t have to modify the file database.yml, I copied it to my EC2 instance and then I added it to .gitignore.
Then, I added a capistrano’s task in deploy.rb, to link database.yml to the current directory of deployment:

# copy db config
after "deploy:update_code", :copy_db_config
desc "copy db config file"
task :copy_db_config do
  run "ln -s ~/path/where/I/copied/database.yml #{release_path}/config/database.yml"
end

Hope this help.