user.rb

class User < ActiveRecord::Base
  def postal_code1
    postal_code.split('-', 2).first || ''
  end
  def postal_code2
    postal_code.split('-', 2).second || ''
  end
  def postal_code1=(value)
    splitted = postal_code.split('-', 2)
    splitted[0] = value
    self.postal_code = splitted.join('-')
  end
  def postal_code2=(value)
    splitted = postal_code.split('-', 2)
    splitted[1] = value
    self.postal_code = splitted.join('-')
  end

  def locations=(value)
    write_attribute(:locations, value.join(' '))
  end
  def locations
    read_attribute(:locations).split(' ')
  end
  def locations_text
    read_attribute(:locations)
  end
end