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# How expensive is DCI in Ruby?
# http://news.ycombinator.com/item?id=4997498

RUBY_VERSION    # => "1.9.3"
RUBY_PATCHLEVEL # => 362
RUBY_PLATFORM   # => "x86_64-darwin12.2.0"

require 'benchmark'
require 'delegate'
require 'forwardable'

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@font-face {
    font-family: SegoeUI;
    src:
        local("Segoe UI Light"),
        url(//c.s-microsoft.com/static/fonts/segoe-ui/west-european/light/latest.woff2) format("woff2"),
        url(//c.s-microsoft.com/static/fonts/segoe-ui/west-european/light/latest.woff) format("woff"),
        url(//c.s-microsoft.com/static/fonts/segoe-ui/west-european/light/latest.ttf) format("truetype");
    font-weight: 100;
}

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# https://stackoverflow.com/questions/34424154/rails-validate-uniqueness-of-two-columns-together

# answer 1
class AddUniqueIndexToReleases < ActiveRecord::Migration
  def change
    add_index :releases, [:country, :medium], unique: true
  end
end

class Release < ActiveRecord::Base

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# Under STI, find the top 10 accounts with the greatest balances
# with just one query.

top_accounts = Account.order(balance: :desc).limit(10)

# Under MTI, we need to query all accounts and sort them in memory:

top_corporate_accts =  CorporateAccount.order(balance: :desc).limit(10)
top_sb_accts =  SmallBusinessAccount.order(balance: :desc).limit(10)
top_personal_accts =  PersonalAccount.order(balance: :desc).limit(10)

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# Suppose the AccountHolder parent class is used
# to simply have an association with an account so
# both corporations and people can have accounts.

class Account < ActiveRecord::Base
  belongs_to :account_holder
end

class AccountHolder < ActiveRecord::Base
  has_one :account

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class Animal < ActiveRecord::Base
  def eat
  end
end

class Bird < Animal
  set_table_name "birds"
  
  def fly
  end

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class Animal < ActiveRecord::Base
  def eat
  end
end

class Bird < Animal
  def fly
  end
end

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class Account < ActiveRecord::Base
  def withdraw(amount)
    # ...
  end
  
  def deposit(amount)
    # ...
  end
  
  def close!

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class Account < ActiveRecord::Base
  def withdraw(amount)
    # ...
  end
  
  def deposit(amount)
    # ...
  end
  
  def close!

nogtini

require 'delegate'

class Account < Struct.new(:owner, :amount)
end

class MoneyTransferContext < Struct.new(:source, :destination)
  def transfer(amount)
    # applico i ruoli ai modelli "stupidi"
    source_account = SourceRole.new(source)
    destination_account = DestinationRole.new(destination)