Advanced search Form

book.rb

class Book < ApplicationRecord
	belongs_to :category

  def self.search(params)
    books = Book.all
    books = books.where("title LIKE '?'",params[:search]) if params[:search].present?
    books = books.where(category_id: params[:category]).where("price <= ?", params[:price])
  end
	
end

books_controller.rb

def search
	if params[:price].present? && params[:category].present?
		@books = Book.search(params)
	elsif params[:category].present?
    	@books = Book.where(category_id: params[:category]) 
    else
      @books = Book.all
  	end
end

end

index.html.erb

<%= form_tag search_books_path, method: :get do %>
<%= select_tag :category, options_from_collection_for_select(Category.all, :id, :name), :include_blank => "Select Category" %>
<%=number_field_tag :price%>
  <%=text_field_tag :search, nil, placeholder: "search" %>
  <%= submit_tag "Search" %>
<%end%><%end%>