cdemyanovich-20110506-0.txt

Blog Title:  Fast-Talking ActiveRecord Migrations
Author:      Craig Demyanovich
Date:        May 6th, 2011

cdemyanovich-20110506-1.rb

class AddApplicationToCe < ActiveRecord::Migration

  def self.up
    add_column :continuing_educations, :origin_application, :string
    ContinuingEducation.find_each do |ce|
      ce.update_attribute(:origin_application, "bank")
    end
  end

  def self.down
    remove_column :continuing_educations, :origin_application
  end

end

cdemyanovich-20110506-2.rake

==  AddApplicationToCe: migrating =============================================
-- add_column(:continuing_educations, :origin_application, :string)
   -> 2.9832s
==  AddApplicationToCe: migrated (724.5134s) ==================================

cdemyanovich-20110506-3.rb

class AddApplicationToCe < ActiveRecord::Migration
  def self.up
    add_column :continuing_educations, :origin_application, :string

    say_with_time "Setting origin_application for all existing CEs" do
      ContinuingEducation.find_each do |ce|
        ce.update_attribute(:origin_application, "bank")
      end
    end
  end

  ...
end

cdemyanovich-20110506-4.rake

==  AddApplicationToCe: migrating =============================================
-- add_column(:continuing_educations, :origin_application, :string)
   -> 2.1238s
-- Setting origin_application for all existing CEs
   -> 722.3896s
   -> 254703 rows
==  AddApplicationToCe: migrated (724.5134s) ====================================

cdemyanovich-20110506-5.rb

class AddApplicationToCe < ActiveRecord::Migration
  def self.up
    add_column :continuing_educations, :origin_application, :string

    say_with_time "Setting origin_application for all existing CEs" do
      ContinuingEducation.update_all "origin_application = 'bank'"
    end
  end

  ...
end

cdemyanovich-20110506-6.rake

==  AddApplicationToCe: migrating =============================================
-- add_column(:continuing_educations, :origin_application, :string)
   -> 2.1238s
-- Setting origin_application for all existing CEs
   -> 3.5165s
   -> 254703 rows
==  AddApplicationToCe: migrated (5.6485s) ====================================

cdemyanovich-20110506-7.rb

class AddApplicationToCe < ActiveRecord::Migration
  def self.up
    add_column :continuing_educations, :origin_application, :string

    ContinuingEducation.reset_column_information
    say_with_time "Setting origin_application for all existing CEs" do
      ContinuingEducation.update_all "origin_application = 'bank'"
    end
  end

  ...
end