In Rails show method is not getting executed - ruby-on-rails

Question

Frnds I have created a controller, named products_controller and product model and also index.html.erb and show.html.erb
but when i call localhost:3000/products it get the details from database. in the same page i have given a link to show the details of a product clearly. But it is not loading. when i clicks on show link i has to get the details of each product. but localhost:3000/products), it loads to the same page.
result for localhost:3000/products
Model Name Brand Name Price Discount Qty Available
Nokia Lumia Nokia 15000 5.0 25 Show
Samsung galaxy Nexus Samsung 45000 15.0 5 Show
Sony Experia Sony Ericsson 4500 1.0 10 Show
Nikon D5100 Nikon 25500 10.0 100 Show
Panasonic Lumix Panasonic 25500 10.0 104 Show
Olympus Granite Olympus 24520 12.0 45 Show
products_controller.rb
class ProductsController < ApplicationController
def index
#products = Product.select("model_name,brand_name, price, discount, qty_avaliable")
respond_to do |format|
format.html # index.html.erb
format.json { render json: #products }
end
end
#render :text => params and return false
def show
#product = Product.find_by_sql("select model_name,brand_name, price, discount, qty_avaliable from products where prod_id='PR1'")
respond_to do |format|
format.html # show.html.erb
format.json { render json: #product }
end
end
end
product.rb
class Product < ActiveRecord::Base
attr_accessible :prod_id, :model_name, :brand_name, :price, :discount, :qty_avaliable
end
index.html.erb
<p id="notice"><%= notice %></p>
<h1>Products List</h1>
<table>
<tr>
<th>Model Name</th>
<th>Brand Name</th>
<th>Price</th>
<th>Discount</th>
<th>Qty Available</th>
<th></th>
<th></th>
<th></th>
</tr>
<% #products.each do |product| %>
<tr>
<td><%= product.model_name %></td>
<td><%= product.brand_name %></td>
<td><%= product.price %></td>
<td><%= product.discount %></td>
<td><%= product.qty_avaliable %></td>
<td><%= link_to 'Show', Product %></td>
</tr>
<% end %>
</table>
show.html.erb
<p prod_id="notice"><%= notice %></p>
<p>
<b>Model Name:</b>
<%= #product.model_name %>
</p>
<p>
<b>Brand Name:</b>
<%= #product.brand_name %>
</p>
<p>
<b>Price:</b>
<%= #product.price %>
</p>
<p>
<b>Discount:</b>
<%= #product.discount %>
</p>
<p>
<b>Quantity:</b>
<%= #product.qty_avaliable %>
</p>

Answer 1

First thing, why don't you have an id for your model, and why are you doing raw SQL?
It should be:
class ProductsController < ApplicationController
def index
#products = Product.all
respond_to do |format|
format.html # index.html.erb
format.json { render json: #products }
end
end
def show
#product = Product.where(id: params[:id]).first
respond_to do |format|
format.html # show.html.erb
format.json { render json: #product }
end
end
end
And on your views, the link is wrong, you should pass the id for the current product in the iteration
<% #products.each do |product| %>
<tr>
<td><%= product.model_name %></td>
<td><%= product.brand_name %></td>
<td><%= product.price %></td>
<td><%= product.discount %></td>
<td><%= product.qty_avaliable %></td>
<td><%= link_to('Show', product) %></td>
</tr>
<% end %>
link_to will do some meta programming behind the scenes, but its mostly the same than doing
<td><%= link_to('Show', product_path(id: product.id) %></td>

Answer 2

It seems to me, that you should use <%= link_to 'Show', product %> instead of <%= link_to 'Show', Product %> in index.html.erb

Answer 3

Here:
<td><%= link_to 'Show', Product %></td>
You need to use product, which is the block variable, not Product, which is a class.