Mysql用database.ymlを生成する

Rails 
rails new app_name

だと、databese.ymlの中身はsqlite3仕様になってる。
引数にオプションdとデータベース名を渡すと、そのデータベースのdatabase.ymlが出来上がる。

$rails new -d mysql

config/database.yml



# MySQL.  Versions 4.1 and 5.0 are recommended.

# 

# Install the MYSQL driver

#   gem install mysql2

#

# Ensure the MySQL gem is defined in your Gemfile

#   gem 'mysql2'

#

# And be sure to use new-style password hashing:

#   http://dev.mysql.com/doc/refman/5.0/en/old-client.html

development:

  adapter: mysql2

  encoding: utf8

  reconnect: false

  database: shern_development

  pool: 5

  username: root

  password:

  socket: /opt/local/var/run/mysql5/mysqld.sock
# Warning: The database defined as "test" will be erased and

# re-generated from your development database when you run "rake".

# Do not set this db to the same as development or production.

test:

  adapter: mysql2

  encoding: utf8

  reconnect: false

  database: shern_test

  pool: 5

  username: root

  password:

  socket: /opt/local/var/run/mysql5/mysqld.sock
production:

  adapter: mysql2

  encoding: utf8

  reconnect: false

  database: shern_production

  pool: 5

  username: root

  password:

  socket: /opt/local/var/run/mysql5/mysqld.sock
http://www.rubylife.jp/rails/model/index2.html

おまけ

オプションtをつけると、testディレクトリを生成しない。