Postgresql9安装方法和步骤：

1. 在 /etc/apt/sources.list.d/pgdg.list 文件中添加源

deb http://apt.postgresql.org/pub/repos/apt/ precise-pgdg main

2. 跟新软件源

sudo apt-get update

3. 安装postgresql 9.3

sudo apt-get install postgresql-9.3

4. 添加用户

sudo -u postgres psql postgres

5. 设置密码

\password postgres

Rails 相关配置

gem 'pg'  #在gemfile中添加

修改database.yml

# common config
 common: &common
   adapter: postgresql
   encoding: utf8
   pool: 10
   username: postgres
   password: password
   host: localhost

# development config
 development:
   database: kindergarten_development
   <<: *common

# test config
 test:
   database: kindergarten_test
   <<: *common

#production config
 production:
   <<: *common
   database: kindergarten