Managing `database.yml` Securely:http://www.simonecarletti.com/blog/2009/06/capistrano-and-database-yml/

database.yml

base: &base                                                                                                                                  
  adapter: sqlite3
  timeout: 5000
development:
  database: <%= shared_path %>/db/development.sqlite3
  <<: *base
test:
  database: <%= shared_path %>/db/test.sqlite3
  <<: *base
production:
  adapter: mysql2
  host: <%= Capistrano::CLI.ui.ask("Enter MySQL database host ip: ") %>
  database: <%= application %>
  username: <%= Capistrano::CLI.ui.ask("Enter MySQL database usename: ") %>
  password: <%= Capistrano::CLI.ui.ask("Enter MySQL database password: ") %>
  encoding: utf8
  pool: 5
  timeout: 5000
  reconnect: false