Ruby on Rails 3: How to access an attribute of each record in a has_many query

I wasn't sure how to phrase it in the title, but what I'm trying to do the following. I have 2 models that have the following relationships:

class Campaign < ActiveRecord::Base
   has_many :points
end

class Point < ActiveRecord::Base
   belongs_to :campaign
end

Now, the Point model has a "locale" attribute and I want to be able to put all the "locales" of every point of a specific campaign into an array, or collection, or whatever without having to do something like

locales = Array.new
campaign.points.each do |p|
   locales << p.locale
end

I was thinking of something along the lines of campaign.points.locales. Is there some nice Rails way of doing this query, or do I ju开发者_开发技巧st have to iterate over the collection?

Thanks for any help.

EDIT: Also because the relationship is actually a "has_many through" relationship, this method doesn't work, as I get many repeated locales if I try to iterate in that simple way. It sounds like it should be some type of join, but I'm not sure.

I'd do:

campaign.points.map(&:locale)

campaign.points.map {|p| p.locale}

should do the trick.

You could do what those guys said. Put a .uniq at the end of them and end up with the correct solution, or;

let me lead you astray with ActiveRecord fun (and possibly failure, since I can't test to see if it works here). But you'll be able to run campaign.points.locales just like you wanted.

class Campaign < ActiveRecord::Base
  has_many :points do
    def locales
      select('DISTINCT(locale)').map(&:locale)
    end
  end
end