Rails內建的資料庫是採用SQLite，資料庫的設定檔在此目錄下:config/database.yml
# SQLite version 3.x
# gem install sqlite3
#
# Ensure the SQLite 3 gem is defined in your Gemfile
# gem 'sqlite3'
development:
adapter: sqlite3
database: db/development.sqlite3
pool: 5
timeout: 5000
# 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: sqlite3
database: db/test.sqlite3
pool: 5
timeout: 5000
production:
adapter: sqlite3
database: db/production.sqlite3
pool: 5
timeout: 5000
建立一個Model
$>rails g model users account:string password:string
invoke active_record
create db/migrate/20120520124738_create_users.rb
create app/models/users.rb
invoke test_unit
create test/unit/users_test.rb
create test/fixtures/users.yml
使用migrate建立資料表
$> bundle exec rake db:migrate
== CreateUsers: migrating ====================================================
-- create_table(:users)
-> 0.0014s
== CreateUsers: migrated (0.0015s) ===========================================
新增一個descript欄位到users表格
rails g migration add_descript_to_users
invoke active_record
create db/migrate/20120520125033_add_descript_to_users.rb
執行migrate將剛新增的欄位加入
$>bundle exec rake db:migrate
== AddDescriptToUsers: migrating =============================================
== AddDescriptToUsers: migrated (0.0000s) ====================================
TIP:Rails會知道哪些已經執行過migration，所以只會執行一次
Rake指令集
rake db:create # to create database
rake db:migrate # to create tables based on your migration
