Question

I’ve been struggling with rails models a bit and could use some guidance. I have two models: Package and Package_item. Packages have many package_items associated to them and I’m trying to figure out how to return the package information along with the array of packge_items in a single method.

class Package < ActiveRecord::Base
  has_many :package_item

  def self.dump
    Package.find(:all,
        :select => "packages.*, packge_items.*")
  end
end

class PackageItem < ActiveRecord::Base
  belongs_to :package
  belongs_to :product
end

I created Package.dump and it isn’t returning the package_items. What am I missing here?

Answer 1

You want this:

Package.includes( :package_items ).all

(Note: Passing a second option to find is officially deprecated, and passing :all, :first, etc. to find will be deprecated in Rails 3.2 (I think). You should use the finder methods Package.all, Package.first, etc. instead. Basically the only time you should be using find is when you have an ID or IDs to pass as the only parameter(s).

If you want you can create a scope for this, which is often preferable to explicitly defining a class method:

class Package < ActiveRecord::Base
  has_many :package_items

  scope :with_items, includes( :package_items )
end

Then you can just call e.g. Package.with_items.