method_with_feature_flags.rb

class Moviegoer < ActiveRecord::Base
  # here's version n+1, using Setler gem for feature flag:
  scope :old_schema, where :migrated => false
  scope :new_schema, where :migrated => true
  def self.find_matching_names(string)
    if Featureflags.new_name_schema
      Moviegoer.new_schema.where('last_name LIKE :s OR first_name LIKE :s',
        :s => "%#{string}%") +
        Moviegoer.old_schema.where('name like ?', "%#{string}%")
    else # use only old schema
      Moviegoer.where('name like ?', "%#{string}%")
    end
  end
  # automatically update records to new schema when they are saved
  before_save :update_schema, :unless => lambda { |m| m.migrated? }
  def update_schema
    if name =~ /^(.*)\s+(.*)$/
      self.first_name = $1
      self.last_name = $2
    end
    self.migrated = true
  end
end