ActiveAdmin limit records on Index page - ruby-on-rails

Question

I have some 10,000+ records in my model. In active_admin index page for that model I have set config.paginate = false. So all the 10,000+ records are shown by default.
How can I limit the number to say last 500 records. I have tried using the below method described here, but its not doing anything to the index page.
ActiveAdmin.register Post do
controller do
def scoped_collection
Post.all.limit(500)
end
end
end

Answer 1

set custom # of rows on page with controller before_filter
controller do
before_filter :set_per_page_var, :only => [:index]
def set_per_page_var
session[:per_page]=params[:per_page]||30
#per_page = session[:per_page]
end
end
and render sidebar with corresponding text input (you can render it as a drop-list)
#...
sidebar('Rows on page', :only => :index) do
form do |f|
f.text_field nil, 'per_page', :value => session[:per_page]
end
end

Answer 2

The issue is this code in Active Admin:
module ActiveAdmin
class ResourceController < BaseController
module DataAccess
def per_page
return max_csv_records if request.format == 'text/csv'
return max_per_page if active_admin_config.paginate == false
#per_page || active_admin_config.per_page
end
def max_csv_records
10_000
end
def max_per_page
10_000
end
end
end
end
When the paginate config option is set to false, it defaults to the number value returned by max_per_page. If you're fine with overriding it globally, you can put this in an initializer:
# config/initializers/active_admin_data_access.rb
module ActiveAdmin
class ResourceController < BaseController
module DataAccess
def max_per_page
500 # was 10,000
end
end
end
end

Answer 3

I was looking for an answer to this same question. I was unable to limit the number of records, so instead I have opted for putting a default value in one of my filters that guarantees an empty page when it loads.
(NOTE: I stole this idea from this stackoverflow question here:: Set ActiveAdmin filter default value )
Example::
In this example, I set a filter called "my_filter_id" equal to "0" in the "before_filter" method if all of the parameters are blank.
ActiveAdmin.register MyModel do
before_filter my_filter_id: :index do
params[:q] = {my_filter_id_eq: 0} if params[:commit].blank?
end
end

Answer 4

Use
Post.limit(500) instead of Post.all.limit(500) so it will minimize the latency.
controller do
def scoped_collection
Post.limit(500)
end
end
index :pagination_total => false do
selectable_column
column :id
column :user_name
column :country
column :city
end
Hope this will help someone.

Answer 5

Try below code. Replace something with your model name.
result = Something.find(:all, :order => "id desc", :limit => 5)
while !result.empty?
puts result.pop
end