64 lines
1.6 KiB
Ruby
64 lines
1.6 KiB
Ruby
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#---
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# Excerpted from "Agile Web Development with Rails",
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# published by The Pragmatic Bookshelf.
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# Copyrights apply to this code. It may not be used to create training material,
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# courses, books, articles, and the like. Contact us if you are in doubt.
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# We make no guarantees that this code is fit for any purpose.
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# Visit http://www.pragmaticprogrammer.com/titles/rails4 for more book information.
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#---
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$: << File.dirname(__FILE__)
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require "connect"
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require "logger"
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#ActiveRecord::Base.logger = Logger.new(STDERR)
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require "rubygems"
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require "active_record"
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ActiveRecord::Schema.define do
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create_table :employees, :force => true do |t|
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t.string :name
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t.integer :manager_id
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t.integer :mentor_id
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end
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end
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class Employee < ActiveRecord::Base
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belongs_to :manager,
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:class_name => "Employee",
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:foreign_key => "manager_id"
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belongs_to :mentor,
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:class_name => "Employee",
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:foreign_key => "mentor_id"
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has_many :mentored_employees,
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:class_name => "Employee",
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:foreign_key => "mentor_id"
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has_many :managed_employees,
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:class_name => "Employee",
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:foreign_key => "manager_id"
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end
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Employee.delete_all
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adam = Employee.create(:name => "Adam")
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beth = Employee.create(:name => "Beth")
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clem = Employee.new(:name => "Clem")
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clem.manager = adam
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clem.mentor = beth
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clem.save!
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dawn = Employee.new(:name => "Dawn")
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dawn.manager = adam
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dawn.mentor = clem
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dawn.save!
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p adam.managed_employees.map {|e| e.name} # => [ "Clem", "Dawn" ]
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p adam.mentored_employees # => []
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p dawn.mentor.name # => "Clem"
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