生成 Controller (route views helpers assets)

rails generate controller Welcome index

查看路由

rails routes

生成 Model

 rails generate model Article title:string text:text

生成 Mailer

rails generate mailer UserMailer

创建 Database与表

rails db:create

rails db:migrate

删除已创建表

class CreateUsers < ActiveRecord::Migration[5.1]  def change    drop_table :users # delete table before create    create_table :users do |t|      t.string :name      t.string :email      t.string :password_digest      t.timestamps    end  endend

向Database 中已存在表添加 Column

rails g migration AddAuthTokenToUsers auth_token:string

db/migrate/20180302143136_add_auth_token_to_users.rb

class AddAuthTokenToUsers < ActiveRecord::Migration[5.1]  def change    add_column :users, :auth_token, :string  endend

向Database 中已存在表删除 Column

class ChangeThingsInComments < ActiveRecord::Migration[5.1]  def change    add_column :comments, :user_id, :integer    remove_column :comments, :username    remove_column :comments, :email  endend