Private method select called for class - Rails - ruby-on-rails

Question

I have the following code inside my controller:
array = Contact.select(:name).distinct
The idea is that this would create an array of all Contact models with a unique :name attribute. However, it's throwing this error:
NoMethodError (private method 'select' called for Contact:Class)
What's the misunderstanding here? For what it's worth, the method calling this line of code is not defined in the controller as private.
EDIT:
Here's the actual code:
Controller
class FluidsurveysController < ApplicationController
def index
end
def import_contacts
#survey_provider = FluidsurveysProviders::SurveyProvider.new()
#current_month = Time.new.strftime("%B%Y%d")
fs_contact_list_array = csv_to_array(params[:file].tempfile)
#fs_contacts_array = []
fs_contact_list_array.each do |hash|
#fs_contacts_array << Contact.new(hash)
end
array = Contact.select(:name).distinct
end
end
Model
class Contact
include ActiveModel::Model
attr_reader :client_id, :client_name, :branch_id, :branch, :short_name, :unit_id, :membership_id,
:first_name, :last_name, :date_of_birth, :change_date_time, :membership_type,
:home_phone, :email_address, :anniversary_years
def initialize(fs_contact_hash = {})
#client_id = fs_contact_hash.fetch('ClientID')
#client_name = fs_contact_hash.fetch('ClientName')
#branch_id = fs_contact_hash.fetch('branchID1')
#branch = fs_contact_hash.fetch('branch')
#name = fs_contact_hash.fetch('ShortName')
#unit_id = fs_contact_hash.fetch('UnitID')
#membership_id = fs_contact_hash.fetch('MemberID')
#first_name = fs_contact_hash.fetch('FirstName')
#last_name = fs_contact_hash.fetch('LastName')
#date_of_birth = fs_contact_hash.fetch('DateOfBirth')
#change_date_time = fs_contact_hash.fetch('ChangeDateTime')
#membership_type = fs_contact_hash.fetch('MembershipType')
#home_phone = fs_contact_hash.fetch('HomePhone')
#email_address = fs_contact_hash.fetch('EMail1')
#anniversary_years = fs_contact_hash.fetch('Years')
end
end

Answer 1

Based on your error message I am pretty sure your model is not an ActiveRecord Object.
If you want to make use of ActiveRecord#select, define your model like this.
class Contact < ActiveRecord::Base
Also you need to define your attributes in a database instead of via attr_reader to access them through ActiveRecord. See http://guides.rubyonrails.org/getting_started.html#running-a-migration

Answer 2

You seem to be using an older version of Rails, specifically version 2.3.whatever. There, the select method is indeed private on the ActiveRecord model classes (as it is inherited from the Kernel module which is part of every Ruby object and serves a wholly different purpose) and thus isn't intended to be used like it is done in Rails 3 and Rails 4.
In Rails 2.3, you can achieve similar results using this syntax:
Contact.all(:select => "DISTINCT name")
This will return an array of Contacts which have only the name attribute set.