19 ActiveRecord: Relationships Between Tables 17 Migration
echo "Order.column_names" | IRBRC=tmp/irbrc rails console
Loading development environment (Rails 3.0.15)
>> Order.column_names
=> ["id", "name", "address", "email", "pay_type", "created_at", "updated_at", "customer_email", "placed_at", "attn", "order_type", "ship_class", "amount", "state"]
>>
echo "Order.columns_hash[\"pay_type\"]" | IRBRC=tmp/irbrc rails console
Loading development environment (Rails 3.0.15)
>> Order.columns_hash["pay_type"]
=> #<ActiveRecord::ConnectionAdapters::SQLiteColumn:0x7ffe9dd997b8 @type=:string, @sql_type="varchar(10)", @name="pay_type", @scale=nil, @limit=10, @precision=nil, @primary=false, @null=true, @default=nil>
>>
sqlite3> select * from orders limit 1
id = 1
name = Dave Thomas
address = 123 Main St
email = customer@example.com
pay_type = check
created_at = 2012-06-29 19:12:46.938145
updated_at = 2012-06-29 19:12:46.938145
customer_email =
placed_at = 2012-06-29 19:16:43.257658
attn =
order_type =
ship_class = priority
amount =
state =
echo "Product.find(:first).updated_at_before_type_cast" | IRBRC=tmp/irbrc rails console
Loading development environment (Rails 3.0.15)
>> Product.find(:first).updated_at_before_type_cast
=> "2012-06-29 19:11:41.032049"
>>
irb e1/ar/new_examples.rb
>> $: << File.dirname(__FILE__)
=> ["/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/will_paginate-3.0.3/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/test-unit-2.5.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/sqlite3-1.3.6/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/mysql-2.8.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/mysql-2.8.1/ext", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/minitest-3.2.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/jquery-rails-0.2.7/lib", "/home/rubys/git/rails/lib", "/home/rubys/git/rails/railties/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/thor-0.14.6/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rdoc-3.12/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/json-1.7.3/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/htmlentities-4.3.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/haml-3.1.6/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/capistrano-2.12.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/net-ssh-gateway-1.1.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/net-sftp-2.0.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/net-scp-1.0.4/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/net-ssh-2.5.2/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/highline-1.6.13/lib", "/home/rubys/git/rails/activeresource/lib", "/home/rubys/git/rails/activerecord/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/arel-2.0.10/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/activemerchant-1.10.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/braintree-2.16.0/lib", "/home/rubys/git/rails/actionmailer/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/mail-2.2.19/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/treetop-1.4.10/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/polyglot-0.3.3/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/mime-types-1.19/lib", "/home/rubys/git/rails/actionpack/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/tzinfo-0.3.33/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rack-test-0.5.7/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rack-mount-0.6.14/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rack-1.2.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/erubis-2.6.6/lib", "/home/rubys/git/rails/activemodel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/i18n-0.5.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/builder-2.1.2/lib", "/home/rubys/git/rails/activesupport/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/abstract-1.0.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rake-0.9.2.2/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/bundler-1.1.3/lib", "/home/rubys/git/gorp/lib", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/site_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/site_ruby/1.8/x86_64-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/site_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/vendor_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/vendor_ruby/1.8/x86_64-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/vendor_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/1.8/x86_64-linux", ".", "/home/rubys/git/awdwr/edition3/data/code/e1/ar"]
>> require "connect"
=> true
?> require "rubygems"
=> false
>> require "active_record"
=> false
>> class Order < ActiveRecord::Base
>> end
=> nil
?> an_order = Order.new
=> #<Order id: nil, name: nil, address: nil, email: nil, pay_type: nil, created_at: nil, updated_at: nil, customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>
>> an_order.name = "Dave Thomas"
=> "Dave Thomas"
>> an_order.email = "dave@example.com"
=> "dave@example.com"
>> an_order.address = "123 Main St"
=> "123 Main St"
>> an_order.pay_type = "check"
=> "check"
>> an_order.save
=> true
?> Order.new do |o|
?> o.name = "Dave Thomas"
>> # . . .
?> o.save
>> end
=> #<Order id: 4, name: "Dave Thomas", address: nil, email: nil, pay_type: nil, created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>
?> an_order = Order.new(
?> :name => "Dave Thomas",
?> :email => "dave@example.com",
?> :address => "123 Main St",
?> :pay_type => "check")
=> #<Order id: nil, name: "Dave Thomas", address: "123 Main St", email: "dave@example.com", pay_type: "check", created_at: nil, updated_at: nil, customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>
>> an_order.save
=> true
?> an_order = Order.new
=> #<Order id: nil, name: nil, address: nil, email: nil, pay_type: nil, created_at: nil, updated_at: nil, customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>
>> an_order.name = "Dave Thomas"
=> "Dave Thomas"
>> # ...
?> an_order.save
=> true
>> puts "The ID of this order is #{an_order.id}"
The ID of this order is 6
=> nil
?> an_order = Order.create(
?> :name => "Dave Thomas",
?> :email => "dave@example.com",
?> :address => "123 Main St",
?> :pay_type => "check")
=> #<Order id: 7, name: "Dave Thomas", address: "123 Main St", email: "dave@example.com", pay_type: "check", created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>
?> orders = Order.create(
?> [ { :name => "Dave Thomas",
?> :email => "dave@example.com",
?> :address => "123 Main St",
?> :pay_type => "check"
>> },
?> { :name => "Andy Hunt",
?> :email => "andy@example.com",
?> :address => "456 Gentle Drive",
?> :pay_type => "po"
>> } ] )
=> [#<Order id: 8, name: "Dave Thomas", address: "123 Main St", email: "dave@example.com", pay_type: "check", created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>, #<Order id: 9, name: "Andy Hunt", address: "456 Gentle Drive", email: "andy@example.com", pay_type: "po", created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>]
>> >> => nil
irb e1/ar/find_examples.rb
>> $: << File.dirname(__FILE__)
=> ["/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/will_paginate-3.0.3/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/test-unit-2.5.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/sqlite3-1.3.6/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/mysql-2.8.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/mysql-2.8.1/ext", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/minitest-3.2.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/jquery-rails-0.2.7/lib", "/home/rubys/git/rails/lib", "/home/rubys/git/rails/railties/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/thor-0.14.6/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rdoc-3.12/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/json-1.7.3/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/htmlentities-4.3.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/haml-3.1.6/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/capistrano-2.12.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/net-ssh-gateway-1.1.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/net-sftp-2.0.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/net-scp-1.0.4/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/net-ssh-2.5.2/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/highline-1.6.13/lib", "/home/rubys/git/rails/activeresource/lib", "/home/rubys/git/rails/activerecord/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/arel-2.0.10/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/activemerchant-1.10.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/braintree-2.16.0/lib", "/home/rubys/git/rails/actionmailer/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/mail-2.2.19/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/treetop-1.4.10/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/polyglot-0.3.3/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/mime-types-1.19/lib", "/home/rubys/git/rails/actionpack/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/tzinfo-0.3.33/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rack-test-0.5.7/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rack-mount-0.6.14/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rack-1.2.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/erubis-2.6.6/lib", "/home/rubys/git/rails/activemodel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/i18n-0.5.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/builder-2.1.2/lib", "/home/rubys/git/rails/activesupport/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/abstract-1.0.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rake-0.9.2.2/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/bundler-1.1.3/lib", "/home/rubys/git/gorp/lib", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/site_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/site_ruby/1.8/x86_64-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/site_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/vendor_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/vendor_ruby/1.8/x86_64-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/vendor_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/1.8/x86_64-linux", ".", "/home/rubys/git/awdwr/edition3/data/code/e1/ar"]
>> require "connect"
=> true
>> require "logger"
=> false
>> ActiveRecord::Base.logger = Logger.new(STDERR)
=> #<Logger:0x7f98a8411d18 @level=0, @default_formatter=#<Logger::Formatter:0x7f98a8411cc8 @datetime_format=nil>, @logdev=#<Logger::LogDevice:0x7f98a8411c78 @filename=nil, @mutex=#<Logger::LogDevice::LogDeviceMutex:0x7f98a8411c28 @mon_owner=nil, @mon_waiting_queue=[], @mon_entering_queue=[], @mon_count=0>, @dev=#<IO:0x7f98ae69caa0>, @shift_size=nil, @shift_age=nil>, @formatter=nil, @progname=nil>
?> require "rubygems"
=> false
>> require "active_record"
=> false
>> require "pp"
=> true
>> @params = {}
=> {}
>> def params
>> @params
>> end
=> nil
?> class Order < ActiveRecord::Base
>> named_scope :check, :conditions => {:pay_type => 'check'}
>> named_scope :cc, :conditions => {:pay_type => 'cc'}
>> named_scope :po, :conditions => {:pay_type => 'po'}
>> end
=> #<Proc:0x00007f98a860db58@/home/rubys/git/rails/activerecord/lib/active_record/named_scope.rb:106>
?> class Order < ActiveRecord::Base
>> named_scope :recent, :conditions => ['created_at > ?', 1.week.ago]
>> named_scope :since, lambda { |range|
?> { :conditions => ['created_at > ?', range] }
>> }
>> end
=> #<Proc:0x00007f98a860db58@/home/rubys/git/rails/activerecord/lib/active_record/named_scope.rb:106>
>> class LineItem < ActiveRecord::Base
>> end
=> nil
>> class Product < ActiveRecord::Base
>> end
=> nil
?> # return an arbitrary order
?> order = Order.find(:first)
*[1m*[36mOrder Load (0.9ms) *[1mSELECT "orders".* FROM "orders" LIMIT 1
=> #<Order id: 1, name: "Dave Thomas", address: "123 Main St", email: "customer@example.com", pay_type: "check", created_at: "2012-06-29 19:12:46", updated_at: "2012-06-29 19:12:46", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>
>> # return an order for Dave
?> order = Order.find(:first, :conditions => "name = 'Dave Thomas'")
*[1m*[35mOrder Load (0.4ms) SELECT "orders".* FROM "orders" WHERE (name = 'Dave Thomas') LIMIT 1
=> #<Order id: 1, name: "Dave Thomas", address: "123 Main St", email: "customer@example.com", pay_type: "check", created_at: "2012-06-29 19:12:46", updated_at: "2012-06-29 19:12:46", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>
>> # return the latest order for Dave
?> order = Order.find(:first,
?> :conditions => "name = 'Dave Thomas'",
?> :order => "id DESC")
*[1m*[36mOrder Load (0.4ms) *[1mSELECT "orders".* FROM "orders" WHERE (name = 'Dave Thomas') ORDER BY id DESC LIMIT 1
=> #<Order id: 8, name: "Dave Thomas", address: "123 Main St", email: "dave@example.com", pay_type: "check", created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>
?> orders = LineItem.find_by_sql("select line_items.* from line_items, orders " +
?> " where order_id = orders.id " +
?> " and orders.name = 'Dave Thomas' ")
*[1m*[35mLineItem Load (0.3ms) select line_items.* from line_items, orders where order_id = orders.id and orders.name = 'Dave Thomas'
=> [#<LineItem id: 1, product_id: 3, order_id: 1, quantity: 1, total_price: 2850, created_at: "2012-06-29 19:12:46", updated_at: "2012-06-29 19:12:46", unit_price: #<BigDecimal:7f98a8151e48,'0.285E2',18(18)>>]
?> orders = Order.find_by_sql("select name, pay_type from orders")
*[1m*[36mOrder Load (0.4ms) *[1mselect name, pay_type from orders
=> [#<Order name: "Dave Thomas", pay_type: "check">, #<Order name: "Joe User", pay_type: "check">, #<Order name: "Dave Thomas", pay_type: "check">, #<Order name: "Dave Thomas", pay_type: nil>, #<Order name: "Dave Thomas", pay_type: "check">, #<Order name: "Dave Thomas", pay_type: nil>, #<Order name: "Dave Thomas", pay_type: "check">, #<Order name: "Dave Thomas", pay_type: "check">, #<Order name: "Andy Hunt", pay_type: "po">]
>> first = orders[0]
=> #<Order name: "Dave Thomas", pay_type: "check">
>> p first.attributes
{"name"=>"Dave Thomas", "pay_type"=>"check"}
=> nil
>> p first.attribute_names
["name", "pay_type"]
=> nil
>> p first.attribute_present?("address")
false
=> nil
?> p Order.all
*[1m*[35mOrder Load (0.8ms) SELECT "orders".* FROM "orders"
[#<Order id: 1, name: "Dave Thomas", address: "123 Main St", email: "customer@example.com", pay_type: "check", created_at: "2012-06-29 19:12:46", updated_at: "2012-06-29 19:12:46", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>, #<Order id: 2, name: "Joe User", address: "123 Main St., Anytown USA", email: "juser@hotmail.com", pay_type: "check", created_at: "2012-06-29 19:13:57", updated_at: "2012-06-29 19:13:57", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>, #<Order id: 3, name: "Dave Thomas", address: "123 Main St", email: "dave@example.com", pay_type: "check", created_at: "2012-06-29 19:19:34", updated_at: "2012-06-29 19:19:34", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>, #<Order id: 4, name: "Dave Thomas", address: nil, email: nil, pay_type: nil, created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>, #<Order id: 5, name: "Dave Thomas", address: "123 Main St", email: "dave@example.com", pay_type: "check", created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>, #<Order id: 6, name: "Dave Thomas", address: nil, email: nil, pay_type: nil, created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>, #<Order id: 7, name: "Dave Thomas", address: "123 Main St", email: "dave@example.com", pay_type: "check", created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>, #<Order id: 8, name: "Dave Thomas", address: "123 Main St", email: "dave@example.com", pay_type: "check", created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>, #<Order id: 9, name: "Andy Hunt", address: "456 Gentle Drive", email: "andy@example.com", pay_type: "po", created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>]
*[1m*[36mSQL (0.4ms) *[1m SELECT name
FROM sqlite_master
WHERE type = 'table' AND NOT name = 'sqlite_sequence'
*[1m*[35mOrder Load (0.4ms) SELECT "orders".* FROM "orders" WHERE "orders"."pay_type" = 'check' LIMIT 1
=> nil
>> p Order.check(:order => "created_on desc").first
#<Order id: 1, name: "Dave Thomas", address: "123 Main St", email: "customer@example.com", pay_type: "check", created_at: "2012-06-29 19:12:46", updated_at: "2012-06-29 19:12:46", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>
=> nil
>> p Order.po.recent.count
*[1m*[36mSQL (0.3ms) *[1mSELECT COUNT(*) FROM "orders" WHERE "orders"."pay_type" = 'po' AND (created_at > '2012-06-22 19:19:39.953228')
1
=> nil
>> p Order.check.find_by_name('Dave Thomas')
*[1m*[35mOrder Load (0.3ms) SELECT "orders".* FROM "orders" WHERE "orders"."pay_type" = 'check' AND "orders"."name" = 'Dave Thomas' LIMIT 1
#<Order id: 1, name: "Dave Thomas", address: "123 Main St", email: "customer@example.com", pay_type: "check", created_at: "2012-06-29 19:12:46", updated_at: "2012-06-29 19:12:46", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>
=> nil
?> p Order.po.recent(:order => :created_at).to_a
*[1m*[36mOrder Load (0.3ms) *[1mSELECT "orders".* FROM "orders" WHERE "orders"."pay_type" = 'po' AND (created_at > '2012-06-22 19:19:39.953228')
[#<Order id: 9, name: "Andy Hunt", address: "456 Gentle Drive", email: "andy@example.com", pay_type: "po", created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>]
=> nil
>> p Order.po.since(1.week.ago).to_a
*[1m*[35mOrder Load (0.3ms) SELECT "orders".* FROM "orders" WHERE "orders"."pay_type" = 'po' AND (created_at > '2012-06-22 19:19:40.086710')
[#<Order id: 9, name: "Andy Hunt", address: "456 Gentle Drive", email: "andy@example.com", pay_type: "po", created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>]
=> nil
>> LineItem.delete_all
*[1m*[36mAREL (146.3ms) *[1mDELETE FROM "line_items" WHERE 1=1
=> 2
>> Product.delete_all
*[1m*[35mAREL (86.7ms) DELETE FROM "products" WHERE 1=1
=> 3
>> p = Product.create(:title => "Programming Ruby", :price => 49.95)
*[1m*[36mAREL (0.6ms) *[1mINSERT INTO "products" ("description", "title", "price", "image_url", "created_at", "updated_at") VALUES (NULL, 'Programming Ruby', 49.95, NULL, '2012-06-29 19:19:40.350507', '2012-06-29 19:19:40.350507')
=> #<Product id: 5, title: "Programming Ruby", description: nil, image_url: nil, created_at: "2012-06-29 19:19:40", updated_at: "2012-06-29 19:19:40", price: #<BigDecimal:7f98a80365e0,'0.4995E2',18(18)>>
>> LineItem.create(:quantity => 2, :unit_price => 49.95, :total_price => 99.90,
?> :product_id => p.id, :order_id => first)
*[1m*[35mAREL (0.8ms) INSERT INTO "line_items" ("created_at", "unit_price", "updated_at", "product_id", "order_id", "quantity", "total_price") VALUES ('2012-06-29 19:19:40.462293', 49.95, '2012-06-29 19:19:40.462293', 5, 1, 2, 99)
=> #<LineItem id: 3, product_id: 5, order_id: 1, quantity: 2, total_price: 99, created_at: "2012-06-29 19:19:40", updated_at: "2012-06-29 19:19:40", unit_price: #<BigDecimal:7f98a80185b8,'0.4995E2',18(18)>>
?> items = LineItem.find_by_sql("select *, " +
?> " quantity*unit_price as total_price, " +
?> " products.title as title " +
?> " from line_items, products " +
?> " where line_items.product_id = products.id ")
*[1m*[36mLineItem Load (0.7ms) *[1mselect *, quantity*unit_price as total_price, products.title as title from line_items, products where line_items.product_id = products.id
=> [#<LineItem id: 5, product_id: 5, order_id: 1, quantity: 2, total_price: 99, created_at: "2012-06-29 19:19:40", updated_at: "2012-06-29 19:19:40", unit_price: #<BigDecimal:7f98a7ff6580,'0.4995E2',18(18)>>]
>> li = items[0]
=> #<LineItem id: 5, product_id: 5, order_id: 1, quantity: 2, total_price: 99, created_at: "2012-06-29 19:19:40", updated_at: "2012-06-29 19:19:40", unit_price: #<BigDecimal:7f98a7ff3010,'0.4995E2',18(18)>>
*[1m*[35mSQL (0.3ms) SELECT COUNT(*) FROM "orders"
>> puts "#{li.title}: #{li.quantity}x#{li.unit_price} => #{li.total_price}"
Programming Ruby: 2x49.95 => 99
=> nil
?> c1 = Order.count
=> 9
>> c2 = Order.count(:conditions => ["name = ?", "Dave Thomas"])
*[1m*[36mSQL (0.4ms) *[1mSELECT COUNT(*) FROM "orders" WHERE (name = 'Dave Thomas')
=> 7
>> c3 = LineItem.count_by_sql("select count(*) " +
?> " from line_items, orders " +
?> " where line_items.order_id = orders.id " +
?> " and orders.name = 'Dave Thomas' ")
*[1m*[35mLineItem Count (0.4ms) select count(*) from line_items, orders where line_items.order_id = orders.id and orders.name = 'Dave Thomas'
=> 1
>> puts "Dave has #{c3} line items in #{c2} orders (#{c1} orders in all)"
Dave has 1 line items in 7 orders (9 orders in all)
=> nil
?> order = Order.find_by_name("Dave Thomas")
*[1m*[36mOrder Load (0.6ms) *[1mSELECT "orders".* FROM "orders" WHERE "orders"."name" = 'Dave Thomas' LIMIT 1
=> #<Order id: 1, name: "Dave Thomas", address: "123 Main St", email: "customer@example.com", pay_type: "check", created_at: "2012-06-29 19:12:46", updated_at: "2012-06-29 19:12:46", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>
>> orders = Order.find_all_by_name("Dave Thomas")
*[1m*[35mOrder Load (1.3ms) SELECT "orders".* FROM "orders" WHERE "orders"."name" = 'Dave Thomas'
=> [#<Order id: 1, name: "Dave Thomas", address: "123 Main St", email: "customer@example.com", pay_type: "check", created_at: "2012-06-29 19:12:46", updated_at: "2012-06-29 19:12:46", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>, #<Order id: 3, name: "Dave Thomas", address: "123 Main St", email: "dave@example.com", pay_type: "check", created_at: "2012-06-29 19:19:34", updated_at: "2012-06-29 19:19:34", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>, #<Order id: 4, name: "Dave Thomas", address: nil, email: nil, pay_type: nil, created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>, #<Order id: 5, name: "Dave Thomas", address: "123 Main St", email: "dave@example.com", pay_type: "check", created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>, #<Order id: 6, name: "Dave Thomas", address: nil, email: nil, pay_type: nil, created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>, #<Order id: 7, name: "Dave Thomas", address: "123 Main St", email: "dave@example.com", pay_type: "check", created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>, #<Order id: 8, name: "Dave Thomas", address: "123 Main St", email: "dave@example.com", pay_type: "check", created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>]
>> orders = Order.find_all_by_email(params['email'])
=> [#<Order id: 4, name: "Dave Thomas", address: nil, email: nil, pay_type: nil, created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>, #<Order id: 6, name: "Dave Thomas", address: nil, email: nil, pay_type: nil, created_at: "2012-06-29 19:19:35", updated_at: "2012-06-29 19:19:35", customer_email: nil, placed_at: "2012-06-29 19:16:43", attn: nil, order_type: nil, ship_class: "priority", amount: nil, state: nil>]
>> o = LineItem.find(:all,
?> :conditions => "pr.title = 'Programming Ruby'",
?> :joins => "inner join products as pr on line_items.product_id = pr.id")
=> [#<LineItem id: 3, product_id: 5, order_id: 1, quantity: 2, total_price: 99, created_at: "2012-06-29 19:19:40", updated_at: "2012-06-29 19:19:40", unit_price: #<BigDecimal:7f98a7f70750,'0.4995E2',18(18)>>]
>> p o.size
1
=> nil
>> LineItem.delete_all
*[1m*[36mOrder Load (0.4ms) *[1mSELECT "orders".* FROM "orders" WHERE "orders"."email" IS NULL
*[1m*[35mLineItem Load (0.3ms) SELECT "line_items".* FROM "line_items" inner join products as pr on line_items.product_id = pr.id WHERE (pr.title = 'Programming Ruby')
=> 1
>> res = Order.update_all("pay_type = 'wibble'")
*[1m*[36mAREL (147.6ms) *[1mDELETE FROM "line_items" WHERE 1=1
=> 9
*[1m*[35mAREL (98.0ms) UPDATE "orders" SET pay_type = 'wibble'
>> p res
9
=> nil
>> res = Order.delete_all(["pay_type = ?", "wibble"])
*[1m*[36mAREL (112.1ms) *[1mDELETE FROM "orders" WHERE (pay_type = 'wibble')
=> 9
>> p res
9
=> nil
irb e1/ar/dump_serialize_table.rb
>> $: << File.dirname(__FILE__)
=> ["/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/will_paginate-3.0.3/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/test-unit-2.5.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/sqlite3-1.3.6/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/mysql-2.8.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/mysql-2.8.1/ext", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/minitest-3.2.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/jquery-rails-0.2.7/lib", "/home/rubys/git/rails/lib", "/home/rubys/git/rails/railties/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/thor-0.14.6/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rdoc-3.12/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/json-1.7.3/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/htmlentities-4.3.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/haml-3.1.6/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/capistrano-2.12.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/net-ssh-gateway-1.1.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/net-sftp-2.0.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/net-scp-1.0.4/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/net-ssh-2.5.2/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/highline-1.6.13/lib", "/home/rubys/git/rails/activeresource/lib", "/home/rubys/git/rails/activerecord/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/arel-2.0.10/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/activemerchant-1.10.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/braintree-2.16.0/lib", "/home/rubys/git/rails/actionmailer/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/mail-2.2.19/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/treetop-1.4.10/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/polyglot-0.3.3/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/mime-types-1.19/lib", "/home/rubys/git/rails/actionpack/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/tzinfo-0.3.33/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rack-test-0.5.7/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rack-mount-0.6.14/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rack-1.2.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/erubis-2.6.6/lib", "/home/rubys/git/rails/activemodel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/i18n-0.5.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/builder-2.1.2/lib", "/home/rubys/git/rails/activesupport/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/abstract-1.0.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rake-0.9.2.2/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/bundler-1.1.3/lib", "/home/rubys/git/gorp/lib", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/site_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/site_ruby/1.8/x86_64-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/site_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/vendor_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/vendor_ruby/1.8/x86_64-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/vendor_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/1.8/x86_64-linux", ".", "/home/rubys/git/awdwr/edition3/data/code/e1/ar"]
>> require 'connect'
=> true
>> require 'rubygems'
=> false
>> require 'active_record'
=> false
>> require 'pp'
=> true
>> ActiveRecord::Schema.define do
?> create_table :purchases, :force => true do |t|
?> t.string :name
>> t.text :last_five
>> end
>> end
-- create_table(:purchases, {:force=>true})
-> 0.1352s
=> nil
?> class Purchase < ActiveRecord::Base
>> serialize :last_five
>> # ...
?> end
=> Object
?> purchase = Purchase.new
=> #<Purchase id: nil, name: nil, last_five: nil>
>> purchase.name = "Dave Thomas"
=> "Dave Thomas"
>> purchase.last_five = [ 'shoes', 'shirt', 'socks', 'ski mask', 'shorts' ]
=> ["shoes", "shirt", "socks", "ski mask", "shorts"]
>> purchase.save
=> true
?> purchase = Purchase.find_by_name("Dave Thomas")
=> #<Purchase id: 1, name: "Dave Thomas", last_five: ["shoes", "shirt", "socks", "ski mask", "shorts"]>
>> pp purchase.last_five
["shoes", "shirt", "socks", "ski mask", "shorts"]
=> nil
>> pp purchase.last_five[3]
"ski mask"
=> nil
>> >> => nil
irb e1/ar/aggregation.rb
>> $: << File.dirname(__FILE__)
=> ["/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/will_paginate-3.0.3/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/test-unit-2.5.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/sqlite3-1.3.6/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/mysql-2.8.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/mysql-2.8.1/ext", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/minitest-3.2.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/jquery-rails-0.2.7/lib", "/home/rubys/git/rails/lib", "/home/rubys/git/rails/railties/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/thor-0.14.6/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rdoc-3.12/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/json-1.7.3/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/htmlentities-4.3.1/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/haml-3.1.6/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/capistrano-2.12.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/net-ssh-gateway-1.1.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/net-sftp-2.0.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/net-scp-1.0.4/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/net-ssh-2.5.2/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/highline-1.6.13/lib", "/home/rubys/git/rails/activeresource/lib", "/home/rubys/git/rails/activerecord/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/arel-2.0.10/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/activemerchant-1.10.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/braintree-2.16.0/lib", "/home/rubys/git/rails/actionmailer/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/mail-2.2.19/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/treetop-1.4.10/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/polyglot-0.3.3/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/mime-types-1.19/lib", "/home/rubys/git/rails/actionpack/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/tzinfo-0.3.33/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rack-test-0.5.7/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rack-mount-0.6.14/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rack-1.2.5/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/erubis-2.6.6/lib", "/home/rubys/git/rails/activemodel/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/i18n-0.5.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/builder-2.1.2/lib", "/home/rubys/git/rails/activesupport/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/abstract-1.0.0/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/rake-0.9.2.2/lib", "/home/rubys/.rvm/gems/ruby-1.8.7-p352/gems/bundler-1.1.3/lib", "/home/rubys/git/gorp/lib", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/site_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/site_ruby/1.8/x86_64-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/site_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/vendor_ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/vendor_ruby/1.8/x86_64-linux", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/vendor_ruby", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/1.8", "/home/rubys/.rvm/rubies/ruby-1.8.7-p352/lib/ruby/1.8/x86_64-linux", ".", "/home/rubys/git/awdwr/edition3/data/code/e1/ar"]
>> require "connect"
=> true
>> require "logger"
=> false
>> require "pp"
=> true
>> #ActiveRecord::Base.logger = Logger.new(STDERR)
?> #require "rubygems"
?> #require_gem "active_record"
?> ActiveRecord::Schema.define do
?> create_table :customers, :force => true do |t|
?> t.datetime :created_at
>> t.decimal :credit_limit, :precision => 10, :scale => 2, :default => 100
>> t.string :first_name
>> t.string :initials
>> t.string :last_name
>> t.datetime :last_purchase
>> t.integer :purchase_count, :default => 0
>> end
>> end
-- create_table(:customers, {:force=>true})
-> 0.2181s
=> nil
?> class LastFive
>> attr_reader :list
>> # Takes a string containing "a,b,c" and
?> # stores [ 'a', 'b', 'c' ]
?> def initialize(list_as_string)
>> @list = list_as_string.split(/,/)
>> end
>> # Returns our contents as a
?> # comma delimited string
?> def last_five
>> @list.join(',')
>> end
>> end
=> nil
?> class Purchase < ActiveRecord::Base
>> composed_of :last_five
>> end
=> #<ActiveRecord::Reflection::AggregateReflection:0x7f500cc81f28 @name=:last_five, @macro=:composed_of, @active_record=Purchase(id: integer, name: string, last_five: text), @options={}>
>> Purchase.delete_all
=> 1
?> Purchase.create(:last_five => LastFive.new("3,4,5"))
=> #<Purchase id: 2, name: nil, last_five: "3,4,5">
>> purchase = Purchase.find(:first)
=> #<Purchase id: 2, name: nil, last_five: "3,4,5">
>> puts purchase.last_five.list[1] #=> 4
4
=> nil
?> class Name
>> attr_reader :first, :initials, :last
>> def initialize(first, initials, last)
>> @first = first
>> @initials = initials
>> @last = last
>> end
>> def to_s
>> [ @first, @initials, @last ].compact.join(" ")
>> end
>> end
=> nil
?> class Customer < ActiveRecord::Base
>> composed_of :name,
?> :class_name => "Name",
?> :mapping =>
?> [ # database ruby
?> %w[ first_name first ],
?> %w[ initials initials ],
?> %w[ last_name last ]
>> ]
>> end
=> #<ActiveRecord::Reflection::AggregateReflection:0x7f500cbea2e0 @name=:name, @macro=:composed_of, @active_record=Customer(id: integer, created_at: datetime, credit_limit: decimal, first_name: string, initials: string, last_name: string, last_purchase: datetime, purchase_count: integer), @options={:mapping=>[["first_name", "first"], ["initials", "initials"], ["last_name", "last"]], :class_name=>"Name"}>
>> Customer.delete_all
=> 0
?> name = Name.new("Dwight", "D", "Eisenhower")
=> #<Name:0x7f500cbd2168 @last="Eisenhower", @initials="D", @first="Dwight">
>> Customer.create(:credit_limit => 1000, :name => name)
=> #<Customer id: 1, created_at: "2012-06-29 19:19:50", credit_limit: #<BigDecimal:7f500cb80de0,'0.1E4',9(18)>, first_name: "Dwight", initials: "D", last_name: "Eisenhower", last_purchase: nil, purchase_count: 0>
>> customer = Customer.find(:first)
=> #<Customer id: 1, created_at: "2012-06-29 19:19:50", credit_limit: #<BigDecimal:7f500cb78e88,'0.1E4',9(18)>, first_name: "Dwight", initials: "D", last_name: "Eisenhower", last_purchase: nil, purchase_count: 0>
>> puts customer.name.first #=> Dwight
Dwight
=> nil
>> puts customer.name.last #=> Eisenhower
Eisenhower
=> nil
>> puts customer.name.to_s #=> Dwight D Eisenhower
Dwight D Eisenhower
=> nil
>> customer.name = Name.new("Harry", nil, "Truman")
=> #<Name:0x7f500cb5c7d8 @last="Truman", @initials=nil, @first="Harry">
>> customer.save
=> true
>> >> => nil