Question

This question is fairly similar to [1], except that I’m using Rails 2.3.5 (yes, old) and a complete newb at RoR. I have two models, Configfile and Signoff.

I want to find all Configfiles where the number of signoffs is < 2. Of course, I could do this by filtering the array manually, but this database is big and it’s fairly slow.

class Configfile < ActiveRecord::Base
  belongs_to :computer
  has_many :signoffs,
           :dependent => :destroy
end

and

class Signoff < ActiveRecord::Base
  belongs_to :configfile
end

This seems like something that should be fairly easy to do in Rails, but I can’t figure it out.
My query looks like this so far, and I haven’t gotten anything that works for limiting it by the number of signoffs.

configs = c.configfiles.find(:all,
                             :include => :signoffs,
                             :order => 'filename')

[1] Rails 3 query on condition of an association's count

Answer 1

Configfile.find(:all, :group=>"configfile_id", :joins=>:signoffs, :having=>"count(*) &lt 2")

Which should give you the same as the equivalent rails3:

Configfile.joins(:signoffs").group("configfiles.id").having("count_all < 2").count(:all)