Rails - Load more with jQuery and Ajax Code snippets - Tutorial link http://josephndungu.com/tutorials/rails-load-more-results-using-jquery-ajax

_user.html.erb

  <div class="record" data-id="<%= user.id %>">
    <p><b>ID: </b> <%= user.id %></p>
    <p><b>Name: </b> <%= user.name %></p>
    <p><b>Location: </b> <%= user.location %> </p>
    <p><%= link_to 'Show', user %> | <%= link_to 'Edit', edit_user_path(user) %> | <%= link_to 'Destroy', user, method: :delete, data: { confirm: 'Are you sure?' } %> </p>
  </div>

index.html.erb

<div class="container">
  <%= render @users %>
</div>
<div class="load-more-container">
        <!-- hide our loading gif image so that we show it when making ajax call via jquery -->
	<%= image_tag "ajax-loader.gif", style: "display:none;", class: "loading-gif" %>
	<%= link_to "Load More", users_path, class: "load-more" %>
</div>

index.js.erb

// append the users partial to our div with class of container
$('.container').append('<%= escape_javascript(render(:partial => @users)) %>')

user.rb

class User < ActiveRecord::Base
	default_scope { order('created_at DESC') }
end

users.js

// when the page is ready for manipulation
$(document).ready(function () {
    // when the load more link is clicked
    $('a.load-more').click(function (e) {

        // prevent the default click action
        e.preventDefault();

        // hide load more link
        $('.load-more').hide();

        // show loading gif
        $('.loading-gif').show();

        // get the last id and save it in a variable 'last-id'
        var last_id = $('.record').last().attr('data-id');

        // make an ajax call passing along our last user id
        $.ajax({

            // make a get request to the server
            type: "GET",
            // get the url from the href attribute of our link
            url: $(this).attr('href'),
            // send the last id to our rails app
            data: {
                id: last_id
            },
            // the response will be a script
            dataType: "script",

            // upon success 
            success: function () {
                // hide the loading gif
                $('.loading-gif').hide();
                // show our load more link
                $('.load-more').show();
            }
        });

    });
});

users_controller.rb

class UsersController < ApplicationController
  before_action :set_user, only: [:show, :edit, :update, :destroy]

  # GET /users
  # GET /users.json
  def index
    # if the id params is present
    if params[:id]
      # get all records with id less than 'our last id'
      # and limit the results to 5
      @users = User.where('id < ?', params[:id]).limit(5)
    else
      @users = User.limit(5)
    end
    respond_to do |format|
      format.html
      format.js
    end
  end
.......
end