1.简介 在rails中用migration可以很方便的管理数据库的结构.可以创建数据库,创建表,删除表,添加字段,删除字段,整理数据. migration就是一系列的class,这些类都继承了ActiveRecord::Migration类. class CreateProducts < ActiveRecord::Migration def up create_table :products do |t| t.string :name t.column :description, :text…

首先得特么建立数据库 : rake db:create 实际问题是没有int应该用integer http://www.rubycc.com/column/rails3.2.3/rails.htm…

目录结构 database.yml development: adapter: sqlite3 database: db/test.db pool: 5 timeout: 5000 001_schema.rb require 'active_record' class Schema <ActiveRecord::Migration def self.up create_table :customers, force: true do |t| t.string :name t.string :ad…

rails -h 查看帮助 Usage: rails new APP_PATH [options] Options: -r, [--ruby=PATH] # Path to the Ruby binary of your choice # Default: D:/Rails/Ruby1.9.3/bin/ruby.exe -b, [--builder=BUILDER] # Path to a application builder (can be a files ystem path or URL…

PS:第一次写的很详细,可惜发布失败,然后全没了,这是第二次,表示只贴代码,剩下的自己领悟好了,这就是所谓的一鼓作气再而衰吧,希望没有第三次. 版本: ruby 2.1.0 rails 4.0.2 nginx 1.5.8 mainline version unicorn 4.7.0 /usr/local/nginx/conf/nginx.conf user NginxUser NginxGroup; worker_processes ; events { worker_connections ;…

最近rails3.2在更改数据库表字段,然后要回滚取消,但在运行rake db:rollback命令,错误: rake aborted! An error has occurred, all later migrations canceled: ActiveRecord::IrreversibleMigration/usr/local/rvm/gems/ruby-1.9.3-p392/gems/activerecord-3.2.14/lib/active_record/migration/com…

*rails uses SQLite for database by default *Built-in command-line DB viewer *Self-contained,server-less,zero-configuration,transactional, relational SQL database. Database Setup: config/database.yml rails db - SQLite console mode Turn headers on and…

原文 :https://www.travisluong.com/ruby-on-rails-mountable-vs-full-engine/一个Rails Engine 本质是一个 Rails application,你可以附加到其他的rails application上提供附加功能.一个Rails Engine是一个Rails应用程序,因为它遵循与“普通”Rails应用程序相同的模型视图控制器模式. rails Engine 和通常的rails application有什么的不同呢,一个ra…

rails学习笔记: rake db 命令行 rake db:*****script/generate model task name:string priority:integer script/generate migration add_description_to_task description:string script/generate migration remove_description_from_task description:string 数据类型 引用# :strin…

Rails Concepts Series: https://gorails.com/series/rails-concepts 基本都是免费的 一些细小的知识点,很有帮助. URL和parameter 的简单解析 做一个app template 使用 Ruby on Rails 的❌页面debug rails5的actioncable和websockets介绍(有多个系列的cable视频) Form的submit方法解释:params[:commit] == value 记录关联中的选项:co…