I have a course with many lesson. Here is my models:

class Course
include Mongoid::Document
has_many :lessons, order:

{position: 1}

end

class Lesson
belongs_to :course
end

The has many relation is ordered with the position field. Everything work fine when I run the follow command:

>> Course.find("503a4d36c32266bdd48f5593").lessons.collect{|l| "#

{l.position}. #{l.name}"}
=> ["1. Session 3", "2. Session 4", "3. Session 1", "4. Session 2"]

But now the same command with the "only" selector will erase my ordering:

>> Course.find("503a4d36c32266bdd48f5593").lessons.only(:name, :position).collect{|l| "#{l.position}

. #

{l.name}

"}
=> ["3. Session 1", "4. Session 2", "1. Session 3", "2. Session 4"]

I missed something ?