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ruby-on-railsmongodbscopemongoidnamed-scope

Mongoid Scope order by syntax please


I'm using the latest mongoid...

How do I do the mongoid equivalent of this active record named_scope:

class Comment
  include Mongoid::Document
  include Mongoid::Timestamps

  embedded_in :post

  field :body, :type => String

  named_scope :recent, :limit => 100, :order => 'created_at DESC'
...
end

Solution

  • It has to be defined like this

    scope :recent, order_by(:created_at => :desc).limit(100)
    

    You can check out the mongoid documentation for scopes here

    From the page

    Named scopes are defined at the class level using a scope macro and can be chained to create result sets in a nice DSL.

    class Person
      include Mongoid::Document
      field :occupation, type: String
      field :age, type: Integer
    
      scope :rock_n_rolla, where(occupation: "Rockstar")
      scope :washed_up, where(:age.gt => 30)
      scope :over, ->(limit) { where(:age.gt => limit) }
    end
    
    # Find all the rockstars.
    Person.rock_n_rolla
    
    # Find all rockstars that should probably quit.
    Person.washed_up.rock_n_rolla
    
    # Find a criteria with Keith Richards in it.
    Person.rock_n_rolla.over(60)