optimistic.rb 1.3 KB

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  1. #---
  2. # Excerpted from "Agile Web Development with Rails",
  3. # published by The Pragmatic Bookshelf.
  4. # Copyrights apply to this code. It may not be used to create training material,
  5. # courses, books, articles, and the like. Contact us if you are in doubt.
  6. # We make no guarantees that this code is fit for any purpose.
  7. # Visit http://www.pragmaticprogrammer.com/titles/rails4 for more book information.
  8. #---
  9. #---
  10. # Excerpted from "Agile Web Development with Rails, 4rd Ed.",
  11. # published by The Pragmatic Bookshelf.
  12. # Copyrights apply to this code. It may not be used to create training material,
  13. # courses, books, articles, and the like. Contact us if you are in doubt.
  14. # We make no guarantees that this code is fit for any purpose.
  15. # Visit http://www.pragmaticprogrammer.com/titles/rails4 for more book information.
  16. #---
  17. $: << File.dirname(__FILE__)
  18. require "connect"
  19. require "rubygems"
  20. require "active_record"
  21. ActiveRecord::Schema.define do
  22. create_table :counters, :force => true do |t|
  23. t.integer :count
  24. t.integer :lock_version, :default => 0
  25. end
  26. end
  27. class Counter < ActiveRecord::Base
  28. end
  29. Counter.delete_all
  30. Counter.create(:count => 0)
  31. count1 = Counter.find(:first)
  32. count2 = Counter.find(:first)
  33. count1.count += 3
  34. count1.save
  35. count2.count += 4
  36. count2.save