rails mongoid follow/unfollow guidance and optimization -

i'ved been trying find ideal solution following in mongoid , found this. habtm mongoid following/follower

for reason, im not sure how optimum , post way in 2011.

if implemented way, followers , following ids kept in array. fine , quick small amount of followers. imagine if there thousands of followers, going through array may not quickest way if u search 1 item in array each time.

base on tutorial link, http://ruby.railstutorial.org/chapters/following-users following recommended put in relationship table, quick lookup when u need check on relationships.

my question code below great mongoid optimization ? need expert advise how u guys dealing relationships when there large amount of followers.

thanks.

class user   include mongoid::document    field :name, type: string    has_and_belongs_to_many :following, class_name: 'user', inverse_of: :followers, autosave: true   has_and_belongs_to_many :followers, class_name: 'user', inverse_of: :following    def follow!(user)     if self.id != user.id && !self.following.include?(user)     self.following << user   end  end    def unfollow!(user)    self.following.delete(user)  end  end 

you create actual follow model (that therefore persisted in own collection) this:

class follow   include mondoid::document    belongs_to :user   belongs_to :followed_user, class_name: 'user'  end  class user   include mongoid::document    field :name, type: string   has_many :follows    def follow!(user)     follows.create(followed_user: user)   end    def unfollow!(user)     follows.where(followed_user_id: user.id).destroy   end end