20 ActiveRecord: Object Life Cycle 18 Active Record: The Basics
irb e1/ar/associations.rb
>> $: << File.dirname(__FILE__)
=> ["/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/sqlite3-ruby-1.3.1/lib", "/home/rubys/git/rails/lib", "/home/rubys/git/rails/railties/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/thor-0.14.0/lib", "/home/rubys/git/rails/activeresource/lib", "/home/rubys/git/rails/activerecord/lib", "/home/rubys/git/rails/actionmailer/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mail-2.2.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/treetop-1.4.8/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/polyglot-0.3.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mime-types-1.16/lib", "/home/rubys/git/rails/actionpack/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/tzinfo-0.3.23/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-test-0.5.4/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-mount-0.6.13/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-1.2.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/erubis-2.6.6/lib", "/home/rubys/git/rails/activemodel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/i18n-0.4.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/builder-2.1.2/lib", "/home/rubys/git/rails/activesupport/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/abstract-1.0.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib", "/home/rubys/git/gorp/lib", "/home/rubys/git/arel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/bundler-1.0.0/lib", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8/i686-linux", ".", "/home/rubys/git/awdwr/data/code/e1/ar"]
>> require "connect"
=> true
>> require "logger"
=> nil
>> #ActiveRecord::Base.logger = Logger.new(STDERR)
?> require "rubygems"
=> nil
>> require "active_record"
=> nil
>> ActiveRecord::Schema.define do
?> create_table :products, :force => true do |t|
?> t.string :title
>> t.text :description
>> t.string :image_url
>> t.decimal :price, :precision => 10, :scale => 2
>> t.datetime :available_at
>> end
>> create_table :line_items, :force => true do |t|
?> t.integer :product_id
>> t.integer :order_id
>> t.integer :quantity
>> t.integer :unit_price, :precision => 8, :scale => 2
>> end
>> end
-- create_table(:products, {:force=>true})
-> 0.0244s
-- create_table(:line_items, {:force=>true})
-> 0.0088s
=> nil
?> class Product < ActiveRecord::Base
>> has_many :line_items
>> end
=> [Product(id: integer, title: string, description: text, image_url: string, price: decimal, available_at: datetime)]
>> class LineItem < ActiveRecord::Base
>> belongs_to :product
>> end
=> nil
>> LineItem.delete_all
=> 0
>> p = Product.create(:title => "Programming Ruby", :available_at => Time.now)
=> #<Product id: 1, title: "Programming Ruby", description: nil, image_url: nil, price: nil, available_at: "2010-09-06 01:16:23">
>> l = LineItem.new
=> #<LineItem id: nil, product_id: nil, order_id: nil, quantity: nil, unit_price: nil>
>> l.id = 2
=> 2
>> l.product = p
=> #<Product id: 1, title: "Programming Ruby", description: nil, image_url: nil, price: nil, available_at: "2010-09-06 01:16:23">
>> l.save!
=> true
>> l = LineItem.new
=> #<LineItem id: nil, product_id: nil, order_id: nil, quantity: nil, unit_price: nil>
>> l.product = p
=> #<Product id: 1, title: "Programming Ruby", description: nil, image_url: nil, price: nil, available_at: "2010-09-06 01:16:23">
>> l.save!
=> true
>> puts "\n\nSimple Belongs to"
Simple Belongs to
=> nil
?> item = LineItem.find(2)
=> #<LineItem id: 2, product_id: 1, order_id: nil, quantity: nil, unit_price: nil>
>> # item.product is the associated Product object
?> puts "Current product is #{item.product.id}"
Current product is 1
=> nil
>> puts item.product.title
Programming Ruby
=> nil
>> item.product = Product.new(:title => "Rails for Java Developers",
?> :description => "...",
?> :image_url => "http://....jpg",
?> :price => 34.95,
?> :available_at => Time.now)
=> #<Product id: nil, title: "Rails for Java Developers", description: "...", image_url: "http://....jpg", price: #<BigDecimal:b6c812f0,'0.3495E2',8(8)>, available_at: "2010-09-06 01:16:23">
>> item.save!
=> true
>> puts "New product is #{item.product.id}"
New product is 2
=> nil
>> puts item.product.title
Rails for Java Developers
=> nil
>> puts "\n\nCreate belongs to"
Create belongs to
=> nil
>> item = LineItem.find(2)
=> #<LineItem id: 2, product_id: 2, order_id: nil, quantity: nil, unit_price: nil>
>> # item.product is the associated Product object
?> puts "Current product is #{item.product.id}"
Current product is 2
=> nil
>> puts item.product.title
Rails for Java Developers
=> nil
?> item.create_product(:title => "Rails Recipes",
?> :description => "...",
?> :image_url => "http://....jpg",
?> :price => 32.95,
?> :available_at => Time.now)
=> #<Product id: 3, title: "Rails Recipes", description: "...", image_url: "http://....jpg", price: #<BigDecimal:b6bd7994,'0.3295E2',8(8)>, available_at: "2010-09-06 01:16:23">
>> puts "New product is #{item.product.id}"
New product is 3
=> nil
>> puts item.product.title
Rails Recipes
=> nil
>> puts "\n\nproduct belongs to"
product belongs to
=> nil
>> item = LineItem.find(2)
=> #<LineItem id: 2, product_id: 2, order_id: nil, quantity: nil, unit_price: nil>
>> # item.product is the associated Product object
?> puts "Current product is #{item.product.id}"
Current product is 2
=> nil
>> puts item.product.title
Rails for Java Developers
=> nil
>> item = LineItem.new()
=> #<LineItem id: nil, product_id: nil, order_id: nil, quantity: nil, unit_price: nil>
>> item.create_product(:title => "Advanced Rails",
?> :description => "...",
?> :image_url => "http://....jpg",
?> :price => 34.95,
?> :available_at => Time.now)
=> #<Product id: 4, title: "Advanced Rails", description: "...", image_url: "http://....jpg", price: #<BigDecimal:b6b97754,'0.3495E2',8(8)>, available_at: "2010-09-06 01:16:23">
>> puts "New product is #{item.product.id}"
New product is 4
=> nil
>> puts item.product.title
Advanced Rails
=> nil
>> item.save!
=> true
>> p item.product(true)
#<Product id: 4, title: "Advanced Rails", description: "...", image_url: "http://....jpg", price: #<BigDecimal:b6b789bc,'0.3495E2',8(8)>, available_at: "2010-09-06 01:16:23">
=> nil
>> puts "============="
=============
=> nil
>> prod = Product.find(item.product_id)
=> #<Product id: 4, title: "Advanced Rails", description: "...", image_url: "http://....jpg", price: #<BigDecimal:b6b6dabc,'0.3495E2',8(8)>, available_at: "2010-09-06 01:16:23">
>> p prod.line_items.size
1
=> nil
irb e1/ar/sti.rb
>> $: << File.dirname(__FILE__)
=> ["/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/sqlite3-ruby-1.3.1/lib", "/home/rubys/git/rails/lib", "/home/rubys/git/rails/railties/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/thor-0.14.0/lib", "/home/rubys/git/rails/activeresource/lib", "/home/rubys/git/rails/activerecord/lib", "/home/rubys/git/rails/actionmailer/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mail-2.2.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/treetop-1.4.8/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/polyglot-0.3.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mime-types-1.16/lib", "/home/rubys/git/rails/actionpack/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/tzinfo-0.3.23/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-test-0.5.4/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-mount-0.6.13/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-1.2.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/erubis-2.6.6/lib", "/home/rubys/git/rails/activemodel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/i18n-0.4.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/builder-2.1.2/lib", "/home/rubys/git/rails/activesupport/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/abstract-1.0.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib", "/home/rubys/git/gorp/lib", "/home/rubys/git/arel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/bundler-1.0.0/lib", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8/i686-linux", ".", "/home/rubys/git/awdwr/data/code/e1/ar"]
>> require "connect"
=> true
>> require "logger"
=> nil
>> ActiveRecord::Base.logger = Logger.new(STDERR)
=> #<Logger:0xb6a76190 @default_formatter=#<Logger::Formatter:0xb6a76168 @datetime_format=nil>, @logdev=#<Logger::LogDevice:0xb6a76140 @filename=nil, @mutex=#<Logger::LogDevice::LogDeviceMutex:0xb6a76118 @mon_entering_queue=[], @mon_count=0, @mon_owner=nil, @mon_waiting_queue=[]>, @dev=#<IO:0xb747e55c>, @shift_size=nil, @shift_age=nil>, @level=0, @formatter=nil, @progname=nil>
>> ActiveRecord::Schema.define do
?> create_table :people, :force => true do |t|
?> t.string :type
>> # common attributes
?> t.string :name
>> t.string :email
>> # attributes for type=Customer
?> t.decimal :balance, :precision => 10, :scale => 2
>> # attributes for type=Employee
?> t.integer :reports_to
>> t.integer :dept
>> # attributes for type=Manager
?> # -- none --
?> end
>> end
-- create_table(:people, {:force=>true})
*[1m*[36mSQL (0.3ms) *[1mselect sqlite_version(*)
*[1m*[35mSQL (1.1ms) SELECT name
FROM sqlite_master
WHERE type = 'table' AND NOT name = 'sqlite_sequence'
*[1m*[36mSQL (7.2ms) *[1mCREATE TABLE "people" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, "type" varchar(255), "name" varchar(255), "email" varchar(255), "balance" decimal(10,2), "reports_to" integer, "dept" integer)
-> 0.0234s
=> nil
?> class Person < ActiveRecord::Base
>> end
=> nil
>> class Customer < Person
>> end
=> nil
>> class Employee < Person
>> belongs_to :boss, :class_name => "Manager", :foreign_key => :reports_to
>> end
=> nil
>> class Manager < Employee
>> end
=> nil
?> Customer.create(:name => 'John Doe', :email => "john@doe.com",
?> :balance => 78.29)
*[1m*[35mSQL (0.4ms) SELECT name
FROM sqlite_master
WHERE type = 'table' AND NOT name = 'sqlite_sequence'
*[1m*[36mSQL (0.4ms) *[1mINSERT INTO "people" ("balance", "dept", "email", "name", "reports_to", "type") VALUES (78.29, NULL, 'john@doe.com', 'John Doe', NULL, 'Customer')
=> #<Customer id: 1, type: "Customer", name: "John Doe", email: "john@doe.com", balance: #<BigDecimal:b6ce8360,'0.7829E2',8(8)>, reports_to: nil, dept: nil>
>> wilma = Manager.create(:name => 'Wilma Flint', :email => "wilma@here.com",
?> :dept => 23)
*[1m*[35mSQL (0.3ms) INSERT INTO "people" ("balance", "dept", "email", "name", "reports_to", "type") VALUES (NULL, 23, 'wilma@here.com', 'Wilma Flint', NULL, 'Manager')
=> #<Manager id: 2, type: "Manager", name: "Wilma Flint", email: "wilma@here.com", balance: nil, reports_to: nil, dept: 23>
>> Customer.create(:name => 'Bert Public', :email => "b@public.net",
?> :balance => 12.45)
*[1m*[36mSQL (0.4ms) *[1mINSERT INTO "people" ("balance", "dept", "email", "name", "reports_to", "type") VALUES (12.45, NULL, 'b@public.net', 'Bert Public', NULL, 'Customer')
=> #<Customer id: 3, type: "Customer", name: "Bert Public", email: "b@public.net", balance: #<BigDecimal:b6c8227c,'0.1245E2',8(8)>, reports_to: nil, dept: nil>
>> barney = Employee.new(:name => 'Barney Rub', :email => "barney@here.com",
?> :dept => 23)
=> #<Employee id: nil, type: "Employee", name: "Barney Rub", email: "barney@here.com", balance: nil, reports_to: nil, dept: 23>
>> barney.boss = wilma
=> #<Manager id: 2, type: "Manager", name: "Wilma Flint", email: "wilma@here.com", balance: nil, reports_to: nil, dept: 23>
>> barney.save!
*[1m*[35mSQL (0.4ms) INSERT INTO "people" ("balance", "dept", "email", "name", "reports_to", "type") VALUES (NULL, 23, 'barney@here.com', 'Barney Rub', 2, 'Employee')
=> true
>> manager = Person.find_by_name("Wilma Flint")
*[1m*[36mPerson Load (0.3ms) *[1mSELECT "people".* FROM "people" WHERE ("people"."name" = 'Wilma Flint') LIMIT 1
=> #<Manager id: 2, type: "Manager", name: "Wilma Flint", email: "wilma@here.com", balance: nil, reports_to: nil, dept: 23>
>> puts manager.class #=> Manager
Manager
=> nil
>> puts manager.email #=> wilma@here.com
wilma@here.com
=> nil
>> puts manager.dept #=> 23
23
=> nil
>> customer = Person.find_by_name("Bert Public")
*[1m*[35mPerson Load (0.3ms) SELECT "people".* FROM "people" WHERE ("people"."name" = 'Bert Public') LIMIT 1
=> #<Customer id: 3, type: "Customer", name: "Bert Public", email: "b@public.net", balance: #<BigDecimal:b6b7d6d8,'0.1245E2',8(8)>, reports_to: nil, dept: nil>
>> puts customer.class #=> Customer
Customer
=> nil
>> puts customer.email #=> b@public.net
b@public.net
=> nil
>> puts customer.balance #=> 12.45
12.45
=> nil
>> b = Person.find_by_name("Barney Rub")
*[1m*[36mPerson Load (0.3ms) *[1mSELECT "people".* FROM "people" WHERE ("people"."name" = 'Barney Rub') LIMIT 1
=> #<Employee id: 4, type: "Employee", name: "Barney Rub", email: "barney@here.com", balance: nil, reports_to: 2, dept: 23>
>> p b.boss
*[1m*[35mManager Load (0.3ms) SELECT "people".* FROM "people" WHERE ("people"."type" = 'Manager') AND ("people"."id" = 2) LIMIT 1
#<Manager id: 2, type: "Manager", name: "Wilma Flint", email: "wilma@here.com", balance: nil, reports_to: nil, dept: 23>
=> nil
irb e1/ar/polymorphic.rb 1
>> $: << File.dirname(__FILE__)
=> ["/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/sqlite3-ruby-1.3.1/lib", "/home/rubys/git/rails/lib", "/home/rubys/git/rails/railties/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/thor-0.14.0/lib", "/home/rubys/git/rails/activeresource/lib", "/home/rubys/git/rails/activerecord/lib", "/home/rubys/git/rails/actionmailer/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mail-2.2.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/treetop-1.4.8/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/polyglot-0.3.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mime-types-1.16/lib", "/home/rubys/git/rails/actionpack/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/tzinfo-0.3.23/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-test-0.5.4/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-mount-0.6.13/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-1.2.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/erubis-2.6.6/lib", "/home/rubys/git/rails/activemodel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/i18n-0.4.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/builder-2.1.2/lib", "/home/rubys/git/rails/activesupport/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/abstract-1.0.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib", "/home/rubys/git/gorp/lib", "/home/rubys/git/arel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/bundler-1.0.0/lib", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8/i686-linux", ".", "/home/rubys/git/awdwr/data/code/e1/ar"]
>> require "connect"
=> true
>> require "logger"
=> nil
>> #ActiveRecord::Base.logger = Logger.new(STDERR)
?> require "rubygems"
=> nil
>> require "active_record"
=> nil
>> if ARGV.empty? or ARGV.first == '1'
>> ActiveRecord::Schema.define do
?> create_table :catalog_entries, :force => true do |t|
?> t.string :name
>> t.datetime :acquired_at
>> t.integer :resource_id
>> t.string :resource_type
>> end
?> create_table :articles, :force => true do |t|
?> t.text :content
>> end
>> create_table :sounds, :force => true do |t|
?> t.binary :content
>> end
>> create_table :images, :force => true do |t|
?> t.binary :content
>> end
>> end
>> end
-- create_table(:catalog_entries, {:force=>true})
-> 0.0215s
-- create_table(:articles, {:force=>true})
-> 0.0041s
-- create_table(:sounds, {:force=>true})
-> 0.0036s
-- create_table(:images, {:force=>true})
-> 0.0040s
=> nil
?> class CatalogEntry < ActiveRecord::Base
>> belongs_to :resource, :polymorphic => true
>> end
=> nil
?> class Article < ActiveRecord::Base
>> has_one :catalog_entry, :as => :resource
>> end
=> nil
>> class Sound < ActiveRecord::Base
>> has_one :catalog_entry, :as => :resource
>> end
=> nil
>> class Image < ActiveRecord::Base
>> has_one :catalog_entry, :as => :resource
>> end
=> nil
>> case ARGV.shift
>> when "1"
>> a = Article.new(:content => "This is my new article")
>> c = CatalogEntry.new(:name => 'Article One', :acquired_at => Time.now)
>> c.resource = a
>> c.save!
?> article = Article.find(1)
>> p article.catalog_entry.name #=> "Article One"
>> cat = CatalogEntry.find(1)
>> resource = cat.resource
>> p resource #=> #<Article:0x640d80 @attributes={"id"=>"1",
>> # "content"=>"This is my new article"}>
?> when "2"
>> c = CatalogEntry.new(:name => 'Article One', :acquired_at => Time.now)
>> c.resource = Article.new(:content => "This is my new article")
>> c.save!
>> c = CatalogEntry.new(:name => 'Image One', :acquired_at => Time.now)
>> c.resource = Image.new(:content => "some binary data")
>> c.save!
>> c = CatalogEntry.new(:name => 'Sound One', :acquired_at => Time.now)
>> c.resource = Sound.new(:content => "more binary data")
>> c.save!
?> CatalogEntry.find(:all).each do |c|
?> puts "#{c.name}: #{c.resource.class}"
>> end
>> else
?> a = Sound.new(:content => "ding!")
>> c = CatalogEntry.new(:name => 'Sound One', :acquired_at => Time.now)
>> c.resource = a
>> c.save!
>> c = CatalogEntry.find 1
>> p c.resource
>> a = Sound.find :first
>> p a.catalog_entry
>> end
"Article One"
#<Article id: 1, content: "This is my new article">
=> nil
sqlite3> select * from articles
id = 1
content = This is my new article
sqlite3> select * from catalog_entries
id = 1
name = Article One
acquired_at = 2010-09-06 01:16:28.334378
resource_id = 1
resource_type = Article
sqlite3> delete from catalog_entries
irb e1/ar/polymorphic.rb 2
>> $: << File.dirname(__FILE__)
=> ["/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/sqlite3-ruby-1.3.1/lib", "/home/rubys/git/rails/lib", "/home/rubys/git/rails/railties/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/thor-0.14.0/lib", "/home/rubys/git/rails/activeresource/lib", "/home/rubys/git/rails/activerecord/lib", "/home/rubys/git/rails/actionmailer/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mail-2.2.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/treetop-1.4.8/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/polyglot-0.3.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mime-types-1.16/lib", "/home/rubys/git/rails/actionpack/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/tzinfo-0.3.23/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-test-0.5.4/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-mount-0.6.13/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-1.2.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/erubis-2.6.6/lib", "/home/rubys/git/rails/activemodel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/i18n-0.4.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/builder-2.1.2/lib", "/home/rubys/git/rails/activesupport/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/abstract-1.0.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib", "/home/rubys/git/gorp/lib", "/home/rubys/git/arel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/bundler-1.0.0/lib", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8/i686-linux", ".", "/home/rubys/git/awdwr/data/code/e1/ar"]
>> require "connect"
=> true
>> require "logger"
=> nil
>> #ActiveRecord::Base.logger = Logger.new(STDERR)
?> require "rubygems"
=> nil
>> require "active_record"
=> nil
>> if ARGV.empty? or ARGV.first == '1'
>> ActiveRecord::Schema.define do
?> create_table :catalog_entries, :force => true do |t|
?> t.string :name
>> t.datetime :acquired_at
>> t.integer :resource_id
>> t.string :resource_type
>> end
?> create_table :articles, :force => true do |t|
?> t.text :content
>> end
>> create_table :sounds, :force => true do |t|
?> t.binary :content
>> end
>> create_table :images, :force => true do |t|
?> t.binary :content
>> end
>> end
>> end
=> nil
?> class CatalogEntry < ActiveRecord::Base
>> belongs_to :resource, :polymorphic => true
>> end
=> nil
?> class Article < ActiveRecord::Base
>> has_one :catalog_entry, :as => :resource
>> end
=> nil
>> class Sound < ActiveRecord::Base
>> has_one :catalog_entry, :as => :resource
>> end
=> nil
>> class Image < ActiveRecord::Base
>> has_one :catalog_entry, :as => :resource
>> end
=> nil
>> case ARGV.shift
>> when "1"
>> a = Article.new(:content => "This is my new article")
>> c = CatalogEntry.new(:name => 'Article One', :acquired_at => Time.now)
>> c.resource = a
>> c.save!
?> article = Article.find(1)
>> p article.catalog_entry.name #=> "Article One"
>> cat = CatalogEntry.find(1)
>> resource = cat.resource
>> p resource #=> #<Article:0x640d80 @attributes={"id"=>"1",
>> # "content"=>"This is my new article"}>
?> when "2"
>> c = CatalogEntry.new(:name => 'Article One', :acquired_at => Time.now)
>> c.resource = Article.new(:content => "This is my new article")
>> c.save!
>> c = CatalogEntry.new(:name => 'Image One', :acquired_at => Time.now)
>> c.resource = Image.new(:content => "some binary data")
>> c.save!
>> c = CatalogEntry.new(:name => 'Sound One', :acquired_at => Time.now)
>> c.resource = Sound.new(:content => "more binary data")
>> c.save!
?> CatalogEntry.find(:all).each do |c|
?> puts "#{c.name}: #{c.resource.class}"
>> end
>> else
?> a = Sound.new(:content => "ding!")
>> c = CatalogEntry.new(:name => 'Sound One', :acquired_at => Time.now)
>> c.resource = a
>> c.save!
>> c = CatalogEntry.find 1
>> p c.resource
>> a = Sound.find :first
>> p a.catalog_entry
>> end
Article One: Article
Image One: Image
Sound One: Sound
=> [#<CatalogEntry id: 2, name: "Article One", acquired_at: "2010-09-06 01:16:30", resource_id: 2, resource_type: "Article">, #<CatalogEntry id: 3, name: "Image One", acquired_at: "2010-09-06 01:16:30", resource_id: 1, resource_type: "Image">, #<CatalogEntry id: 4, name: "Sound One", acquired_at: "2010-09-06 01:16:30", resource_id: 1, resource_type: "Sound">]
sqlite3> select * from articles
id = 1
content = This is my new article
id = 2
content = This is my new article
sqlite3> select * from images
id = 1
content = some binary data
sqlite3> select * from sounds
id = 1
content = more binary data
sqlite3> select * from catalog_entries
id = 2
name = Article One
acquired_at = 2010-09-06 01:16:30.733404
resource_id = 2
resource_type = Article
id = 3
name = Image One
acquired_at = 2010-09-06 01:16:30.858121
resource_id = 1
resource_type = Image
id = 4
name = Sound One
acquired_at = 2010-09-06 01:16:30.870668
resource_id = 1
resource_type = Sound
irb e1/ar/self_association.rb
>> $: << File.dirname(__FILE__)
=> ["/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/sqlite3-ruby-1.3.1/lib", "/home/rubys/git/rails/lib", "/home/rubys/git/rails/railties/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/thor-0.14.0/lib", "/home/rubys/git/rails/activeresource/lib", "/home/rubys/git/rails/activerecord/lib", "/home/rubys/git/rails/actionmailer/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mail-2.2.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/treetop-1.4.8/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/polyglot-0.3.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mime-types-1.16/lib", "/home/rubys/git/rails/actionpack/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/tzinfo-0.3.23/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-test-0.5.4/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-mount-0.6.13/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-1.2.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/erubis-2.6.6/lib", "/home/rubys/git/rails/activemodel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/i18n-0.4.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/builder-2.1.2/lib", "/home/rubys/git/rails/activesupport/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/abstract-1.0.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib", "/home/rubys/git/gorp/lib", "/home/rubys/git/arel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/bundler-1.0.0/lib", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8/i686-linux", ".", "/home/rubys/git/awdwr/data/code/e1/ar"]
>> require "connect"
=> true
>> require "logger"
=> nil
>> #ActiveRecord::Base.logger = Logger.new(STDERR)
?> require "rubygems"
=> nil
>> require "active_record"
=> nil
>> ActiveRecord::Schema.define do
?> create_table :employees, :force => true do |t|
?> t.string :name
>> t.integer :manager_id
>> t.integer :mentor_id
>> end
>> end
-- create_table(:employees, {:force=>true})
-> 0.0198s
=> nil
?> class Employee < ActiveRecord::Base
>> belongs_to :manager,
?> :class_name => "Employee",
?> :foreign_key => "manager_id"
>> belongs_to :mentor,
?> :class_name => "Employee",
?> :foreign_key => "mentor_id"
>> has_many :mentored_employees,
?> :class_name => "Employee",
?> :foreign_key => "mentor_id"
>> has_many :managed_employees,
?> :class_name => "Employee",
?> :foreign_key => "manager_id"
>> end
=> [Employee(id: integer, name: string, manager_id: integer, mentor_id: integer)]
?> Employee.delete_all
=> 0
>> adam = Employee.create(:name => "Adam")
=> #<Employee id: 1, name: "Adam", manager_id: nil, mentor_id: nil>
>> beth = Employee.create(:name => "Beth")
=> #<Employee id: 2, name: "Beth", manager_id: nil, mentor_id: nil>
>> clem = Employee.new(:name => "Clem")
=> #<Employee id: nil, name: "Clem", manager_id: nil, mentor_id: nil>
>> clem.manager = adam
=> #<Employee id: 1, name: "Adam", manager_id: nil, mentor_id: nil>
>> clem.mentor = beth
=> #<Employee id: 2, name: "Beth", manager_id: nil, mentor_id: nil>
>> clem.save!
=> true
>> dawn = Employee.new(:name => "Dawn")
=> #<Employee id: nil, name: "Dawn", manager_id: nil, mentor_id: nil>
>> dawn.manager = adam
=> #<Employee id: 1, name: "Adam", manager_id: nil, mentor_id: nil>
>> dawn.mentor = clem
=> #<Employee id: 3, name: "Clem", manager_id: 1, mentor_id: 2>
>> dawn.save!
=> true
?> p adam.managed_employees.map {|e| e.name} # => [ "Clem", "Dawn" ]
["Clem", "Dawn"]
=> nil
>> p adam.mentored_employees # => []
[]
=> nil
>> p dawn.mentor.name # => "Clem"
"Clem"
=> nil
>> >> => nil
irb e1/ar/acts_as_list.rb
>> $: << File.dirname(__FILE__)
=> ["/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/sqlite3-ruby-1.3.1/lib", "/home/rubys/git/rails/lib", "/home/rubys/git/rails/railties/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/thor-0.14.0/lib", "/home/rubys/git/rails/activeresource/lib", "/home/rubys/git/rails/activerecord/lib", "/home/rubys/git/rails/actionmailer/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mail-2.2.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/treetop-1.4.8/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/polyglot-0.3.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mime-types-1.16/lib", "/home/rubys/git/rails/actionpack/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/tzinfo-0.3.23/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-test-0.5.4/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-mount-0.6.13/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-1.2.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/erubis-2.6.6/lib", "/home/rubys/git/rails/activemodel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/i18n-0.4.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/builder-2.1.2/lib", "/home/rubys/git/rails/activesupport/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/abstract-1.0.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib", "/home/rubys/git/gorp/lib", "/home/rubys/git/arel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/bundler-1.0.0/lib", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8/i686-linux", ".", "/home/rubys/git/awdwr/data/code/e1/ar"]
>> require "connect"
=> true
>> require "logger"
=> nil
>> require "rubygems"
=> nil
>> require "active_record"
=> nil
>> require "./vendor/plugins/acts_as_list/init"
=> nil
>> #ActiveRecord::Base.logger = Logger.new(STDERR)
?> ActiveRecord::Base.connection.instance_eval do
?> create_table :parents, :force => true do |t|
?> end
>> create_table :children, :force => true do |t|
?> t.integer :parent_id
>> t.string :name
>> t.integer :position
>> end
>> end
=> []
?> class Parent < ActiveRecord::Base
>> has_many :children, :order => :position
>> end
=> [Parent(id: integer)]
>> class Child < ActiveRecord::Base
>> belongs_to :parent
>> acts_as_list :scope => :parent
>> end
=> [Child(id: integer, parent_id: integer, name: string, position: integer)]
?> parent = Parent.create
=> #<Parent id: 1>
>> %w{ One Two Three Four}.each do |name|
?> parent.children.create(:name => name)
>> end
=> ["One", "Two", "Three", "Four"]
>> parent.save
=> true
?> def display_children(parent)
>> puts parent.children(true).map {|child| child.name }.join(", ")
>> end
=> nil
?> display_children(parent) #=> One, Two, Three, Four
One, Two, Three, Four
=> nil
>> puts parent.children[0].first? #=> true
true
=> nil
>> two = parent.children[1]
=> #<Child id: 2, parent_id: 1, name: "Two", position: 2>
>> puts two.lower_item.name #=> Three
Three
=> nil
>> puts two.higher_item.name #=> One
One
=> nil
>> parent.children[0].move_lower
=> true
>> display_children(parent) #=> Two, One, Three, Four
Two, One, Three, Four
=> nil
>> parent.children[2].move_to_top
=> true
>> display_children(parent) #=> Three, Two, One, Four
Three, Two, One, Four
=> nil
>> parent.children[2].destroy
=> #<Child id: 1, parent_id: 1, name: "One", position: nil>
>> display_children(parent) #=> Three, Two, Four
Three, Two, Four
=> nil
>> >> => nil
irb e1/ar/acts_as_tree.rb
>> $: << File.dirname(__FILE__)
=> ["/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/sqlite3-ruby-1.3.1/lib", "/home/rubys/git/rails/lib", "/home/rubys/git/rails/railties/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/thor-0.14.0/lib", "/home/rubys/git/rails/activeresource/lib", "/home/rubys/git/rails/activerecord/lib", "/home/rubys/git/rails/actionmailer/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mail-2.2.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/treetop-1.4.8/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/polyglot-0.3.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mime-types-1.16/lib", "/home/rubys/git/rails/actionpack/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/tzinfo-0.3.23/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-test-0.5.4/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-mount-0.6.13/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-1.2.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/erubis-2.6.6/lib", "/home/rubys/git/rails/activemodel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/i18n-0.4.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/builder-2.1.2/lib", "/home/rubys/git/rails/activesupport/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/abstract-1.0.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib", "/home/rubys/git/gorp/lib", "/home/rubys/git/arel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/bundler-1.0.0/lib", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8/i686-linux", ".", "/home/rubys/git/awdwr/data/code/e1/ar"]
>> require "connect"
=> true
>> require "logger"
=> nil
>> require "rubygems"
=> nil
>> require "active_record"
=> nil
>> require "./vendor/plugins/acts_as_tree/lib/active_record/acts/tree.rb"
=> nil
>> require "./vendor/plugins/acts_as_tree/init"
=> nil
>> #ActiveRecord::Base.logger = Logger.new(STDERR)
?> ActiveRecord::Schema.define do
?> create_table :categories, :force => true do |t|
?> t.string :name
>> t.integer :parent_id
>> end
>> end
-- create_table(:categories, {:force=>true})
-> 0.0196s
=> nil
?> class Category < ActiveRecord::Base
>> acts_as_tree :order => "name"
>> end
=> nil
?> root = Category.create(:name => "Books")
=> #<Category id: 1, name: "Books", parent_id: nil>
>> fiction = root.children.create(:name => "Fiction")
=> #<Category id: 2, name: "Fiction", parent_id: 1>
>> non_fiction = root.children.create(:name => "Non Fiction")
=> #<Category id: 3, name: "Non Fiction", parent_id: 1>
>> non_fiction.children.create(:name => "Computers")
=> #<Category id: 4, name: "Computers", parent_id: 3>
>> non_fiction.children.create(:name => "Science")
=> #<Category id: 5, name: "Science", parent_id: 3>
>> non_fiction.children.create(:name => "Art History")
=> #<Category id: 6, name: "Art History", parent_id: 3>
>> fiction.children.create(:name => "Mystery")
=> #<Category id: 7, name: "Mystery", parent_id: 2>
>> fiction.children.create(:name => "Romance")
=> #<Category id: 8, name: "Romance", parent_id: 2>
>> fiction.children.create(:name => "Science Fiction")
=> #<Category id: 9, name: "Science Fiction", parent_id: 2>
>> def display_children(order)
>> puts order.children.map {|child| child.name }.join(", ")
>> end
=> nil
?> display_children(root) # Fiction, Non Fiction
Fiction, Non Fiction
=> nil
>> sub_category = root.children.first
=> #<Category id: 2, name: "Fiction", parent_id: 1>
>> puts sub_category.children.size #=> 3
3
=> nil
>> display_children(sub_category) #=> Mystery, Romance, Science Fiction
Mystery, Romance, Science Fiction
=> nil
>> non_fiction = root.children.find(:first, :conditions => "name = 'Non Fiction'")
=> #<Category id: 3, name: "Non Fiction", parent_id: 1>
>> display_children(non_fiction) #=> Art History, Computers, Science
Art History, Computers, Science
=> nil
>> puts non_fiction.parent.name #=> Books
Books
=> nil
>> >> => nil
irb e1/ar/one_to_one.rb
>> $: << File.dirname(__FILE__)
=> ["/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/sqlite3-ruby-1.3.1/lib", "/home/rubys/git/rails/lib", "/home/rubys/git/rails/railties/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/thor-0.14.0/lib", "/home/rubys/git/rails/activeresource/lib", "/home/rubys/git/rails/activerecord/lib", "/home/rubys/git/rails/actionmailer/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mail-2.2.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/treetop-1.4.8/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/polyglot-0.3.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mime-types-1.16/lib", "/home/rubys/git/rails/actionpack/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/tzinfo-0.3.23/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-test-0.5.4/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-mount-0.6.13/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-1.2.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/erubis-2.6.6/lib", "/home/rubys/git/rails/activemodel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/i18n-0.4.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/builder-2.1.2/lib", "/home/rubys/git/rails/activesupport/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/abstract-1.0.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib", "/home/rubys/git/gorp/lib", "/home/rubys/git/arel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/bundler-1.0.0/lib", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8/i686-linux", ".", "/home/rubys/git/awdwr/data/code/e1/ar"]
>> require "connect"
=> true
>> require "logger"
=> nil
>> #ActiveRecord::Base.logger = Logger.new(STDERR)
?> require "rubygems"
=> nil
>> require "active_record"
=> nil
>> ActiveRecord::Schema.define do
?> create_table :invoices, :force => true do |t|
?> t.integer :order_id
>> end
>> create_table :orders, :force => true do |t|
?> t.string :name
>> t.string :email
>> t.text :address
>> t.string :pay_type
>> t.datetime :shipped_at
>> end
>> end
-- create_table(:invoices, {:force=>true})
-> 0.0211s
-- create_table(:orders, {:force=>true})
-> 0.0085s
=> nil
?> class Order < ActiveRecord::Base
>> has_one :invoice
>> end
=> nil
>> class Invoice < ActiveRecord::Base
>> belongs_to :order
>> end
=> nil
>> Order.create(:name => "Dave", :email => "dave@xxx",
?> :address => "123 Main St", :pay_type => "credit",
?> :shipped_at => Time.now)
=> #<Order id: 1, name: "Dave", email: "dave@xxx", address: "123 Main St", pay_type: "credit", shipped_at: "2010-09-06 01:16:40">
>> order = Order.find(1)
=> #<Order id: 1, name: "Dave", email: "dave@xxx", address: "123 Main St", pay_type: "credit", shipped_at: "2010-09-06 01:16:40">
>> p order.invoice
nil
=> nil
>> invoice = Invoice.new
=> #<Invoice id: nil, order_id: nil>
>> if invoice.save
>> order.invoice = invoice
>> else
?> fail invoice.errors.to_s
>> end
=> #<Invoice id: 1, order_id: 1>
>> p order.invoice
#<Invoice id: 1, order_id: 1>
=> nil
>> o = Order.new
=> #<Order id: nil, name: nil, email: nil, address: nil, pay_type: nil, shipped_at: nil>
>> p o.id
nil
=> nil
>> invoice.order = o
=> #<Order id: nil, name: nil, email: nil, address: nil, pay_type: nil, shipped_at: nil>
>> p o.id
nil
=> nil
>> invoice.save
=> true
>> p o.id
2
=> nil
irb e1/ar/counters.rb
>> $: << File.dirname(__FILE__)
=> ["/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/sqlite3-ruby-1.3.1/lib", "/home/rubys/git/rails/lib", "/home/rubys/git/rails/railties/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/thor-0.14.0/lib", "/home/rubys/git/rails/activeresource/lib", "/home/rubys/git/rails/activerecord/lib", "/home/rubys/git/rails/actionmailer/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mail-2.2.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/treetop-1.4.8/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/polyglot-0.3.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/mime-types-1.16/lib", "/home/rubys/git/rails/actionpack/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/tzinfo-0.3.23/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-test-0.5.4/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-mount-0.6.13/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rack-1.2.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/erubis-2.6.6/lib", "/home/rubys/git/rails/activemodel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/i18n-0.4.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/builder-2.1.2/lib", "/home/rubys/git/rails/activesupport/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/abstract-1.0.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib", "/home/rubys/git/gorp/lib", "/home/rubys/git/arel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p302/gems/bundler-1.0.0/lib", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/site_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby/1.8/i686-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/vendor_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8/i686-linux", ".", "/home/rubys/git/awdwr/data/code/e1/ar"]
>> require "connect"
=> true
>> require "logger"
=> nil
>> #ActiveRecord::Base.logger = Logger.new(STDERR)
?> require "rubygems"
=> nil
>> require "active_record"
=> nil
>> ActiveRecord::Schema.define do
?> create_table :products, :force => true do |t|
?> t.string :title
>> t.text :description
>> # ...
?> t.integer :line_items_count, :default => 0
>> end
>> create_table :line_items, :force => true do |t|
?> t.integer :product_id
>> t.integer :order_id
>> t.integer :quantity
>> t.decimal :unit_price, :precision => 8, :scale => 2
>> end
>> end
-- create_table(:products, {:force=>true})
-> 0.0293s
-- create_table(:line_items, {:force=>true})
-> 0.0081s
=> nil
>> class Product < ActiveRecord::Base
>> has_many :line_items
>> end
=> [Product(id: integer, title: string, description: text, line_items_count: integer)]
?> class LineItem < ActiveRecord::Base
>> belongs_to :product, :counter_cache => true
>> end
=> nil
?> product = Product.create(:title => "Programming Ruby",
?> :description => " ... ")
=> #<Product id: 1, title: "Programming Ruby", description: " ... ", line_items_count: 0>
>> line_item = LineItem.new
=> #<LineItem id: nil, product_id: nil, order_id: nil, quantity: nil, unit_price: nil>
>> line_item.product = product
=> #<Product id: 1, title: "Programming Ruby", description: " ... ", line_items_count: 0>
>> line_item.save
=> true
>> puts "In memory size = #{product.line_items.size}" #=> 0
In memory size = 0
=> nil
>> puts "Refreshed size = #{product.line_items(:refresh).size}" #=> 1
Refreshed size = 1
=> nil
>> LineItem.delete_all
=> 1
>> Product.delete_all
=> 1
?> product = Product.create(:title => "Programming Ruby",
?> :description => " ... ")
=> #<Product id: 2, title: "Programming Ruby", description: " ... ", line_items_count: 0>
>> product.line_items.create
=> #<LineItem id: 2, product_id: 2, order_id: nil, quantity: nil, unit_price: nil>
>> puts "In memory size = #{product.line_items.size}" #=> 1
In memory size = 0
=> nil
>> puts "Refreshed size = #{product.line_items(:refresh).size}" #=> 1
Refreshed size = 1
=> nil
>> >> => nil
20 ActiveRecord: Object Life Cycle 18 Active Record: The Basics