如何在 Rails 之外的 ruby 脚本中使用 ActiveRecord？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/1643875/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
How to use ActiveRecord in a ruby script outside Rails?
提问by Daniel Cukier
I have a small ruby script in which I'd like to use ActiveRecord to easily access a database model. What is the best way to do it?
我有一个小的 ruby 脚本，我想在其中使用 ActiveRecord 轻松访问数据库模型。最好的方法是什么？
回答by Pesto
require 'active_record'
# Change the following to reflect your database settings
ActiveRecord::Base.establish_connection(
adapter: 'mysql2', # or 'postgresql' or 'sqlite3' or 'oracle_enhanced'
host: 'localhost',
database: 'your_database',
username: 'your_username',
password: 'your_password'
)
# Define your classes based on the database, as always
class SomeClass < ActiveRecord::Base
#blah, blah, blah
end
# Now do stuff with it
puts SomeClass.find :all
some_class = SomeClass.new
回答by Andy Henson
It's worth noting that in later versions of activerecord (v3+) you need to require it like so
值得注意的是，在 activerecord (v3+) 的更高版本中，您需要像这样要求它
require "active_record"
回答by Thomas Klemm
You can create a minimal script with an in-memory SQLite database in just a few lines. This answer is also available as a Gist.
只需几行，您就可以使用内存中的 SQLite 数据库创建一个最小的脚本。此答案也可作为 Gist 使用。
Inspired by Jon Leighton's blog poston how to post an awesome ActiveRecord bug report.
灵感来自Jon Leighton 的关于如何发布令人敬畏的 ActiveRecord 错误报告的博客文章。
# Based on http://www.jonathanleighton.com/articles/2011/awesome-active-record-bug-reports/
# Run this script with `$ ruby my_script.rb`
require 'sqlite3'
require 'active_record'
# Use `binding.pry` anywhere in this script for easy debugging
require 'pry'
# Connect to an in-memory sqlite3 database
ActiveRecord::Base.establish_connection(
adapter: 'sqlite3',
database: ':memory:'
)
# Define a minimal database schema
ActiveRecord::Schema.define do
create_table :shows, force: true do |t|
t.string :name
end
create_table :episodes, force: true do |t|
t.string :name
t.belongs_to :show, index: true
end
end
# Define the models
class Show < ActiveRecord::Base
has_many :episodes, inverse_of: :show
end
class Episode < ActiveRecord::Base
belongs_to :show, inverse_of: :episodes, required: true
end
# Create a few records...
show = Show.create!(name: 'Big Bang Theory')
first_episode = show.episodes.create!(name: 'Pilot')
second_episode = show.episodes.create!(name: 'The Big Bran Hypothesis')
episode_names = show.episodes.pluck(:name)
puts "#{show.name} has #{show.episodes.size} episodes named #{episode_names.join(', ')}."
# => Big Bang Theory has 2 episodes named Pilot, The Big Bran Hypothesis.
# Use `binding.pry` here to experiment with this setup.
