rake db:fixtures:load 

To load a subset of your fixtures to your projects db

rake db:fixtures:load FIXTURES=users,stores

If you are not familiar with a star rating system, its simply a method of voting using (usually) 5 stars in a row, which will change colour as you hover over them indicating the level at which to rate something. You may think a simple rollover would accomplish this but difficulty arises because as you rollover each star it should stay highlighted while you light up the next one and so on until the end of the row of stars.

Install the acts_as_rateable plugin.

Run the following from the root of your Rails app to install the plugin

script/plugin install http://juixe.com/svn/acts_as_rateable

or
http://rubyforge.org/projects/rateableplugin/

You can original post at http//:satishchauhan.com

This is posted on satish’s blog

For more details click here

The CSV text-file format is a common choice for both import and export when performing data migrations. What if you want to import CSV files within a Rails application?

Here is the code that allow you to upload CSV data onto the MySQL database from the web interface
This code save data direct to database without saving it to temp file

Controller:

    require 'csv'

   def csv_import 
     @parsed_file=CSV::Reader.parse(params[:dump][:file])
     n=0
     @parsed_file.each  do |row|
     c=CustomerInformation.new
     c.job_title=row[1]
     c.first_name=row[2]
     c.last_name=row[3]
     if c.save
        n=n+1
        GC.start if n%50==0
     end
     flash.now[:message]="CSV Import Successful,  #{n} new records added to data base"
   end

View:
your view will look like

 <% form_for :dump, :url=>{:controller=>"customer_informations", :action=>"csv_import"}, :html => { :multipart => true } do |f| -%>
 <table">
   <tr>
     <td>
      <label for="dump_file">
        Select a CSV File :
      </label>
     </td>
     <td >
       <%= f.file_field :file -%>
     </td>
   </tr>
   <tr>
     <td colspan='2'>
       <%= submit_tag 'Submit' -%>
     </td>
   </tr>
 </table>
<% end -%>

Useful expressions for email address validation

Matches a limited version of the RFC 2822 addr-spec form.

/A(?:[w!#$%&'*+-/=?^`{|}~]+.)*[w!#$%&*+-/=?^`{|}~]+@(?:(?:(?:[a-zA-Z0-9](?:[a-zA-Z0-9-]?!.)){0,61}[a-zA-Z0-9]?.)+[a-zA-Z0-9](?:[a-zA-Z0-9-](?!$)){0,61}a-zA-Z0-9]?)|(?:[(?:(?:[01]?d{1,2}|2[0-4]d|25[0-5]).){3}(?:[01]d{1,2}|2[0-4]d|25[0-5])]))Z/i

satish chauhan

So if you are trying to do a multiple select of checkboxes and using habtm in your project, but when you submit the form, only one value was available in your controller. While you try to edit records in database but because of some error you get back to the pre field form and you found that the checkboxes checked by you gone ,then here’s the solution

Model:

	class Customer < ActiveRecord::Base
		has_and_belongs_to_many :intrests
	end

Controller code:

class CustomersController < ApplicationController
   def create
      if request.post?
         @customer=Customer.new(params[:customer])
         @customer.save
      end
   end

   def edit
      @customer=Customer.find_by_id(params[:id]) if params[:id]
      if @customer
         if request.post?
            if @customer.update_attributes(customer)
               flash.now[:message]="Update successfully "
            end
         end
      else
        flash[:message]="Page requested by you does not exists"
      end
   end
end

Your View:

 <% form_for :customer,  do |f| -%>
    First Name:
      <%= f.text_field :first_name  -%>
    Last Name:
      <%= f.text_field :last_name -%>
      <% for  intr in total_intrests -%>
         <%= check_box_tag "customer[interest_ids][]", "#{intr.id}", interest(intr) -%> # interest is a helper method
         <%= "#{intr.name}" -%>
      <% end -%>
   <% end -%>

helper method

   def interest(i)
      if @customer
         @customer.interests.include?(i)
      else
        false
      end
   end

View generate a checkbox for every interest(all_interest=Interest.find(:all)). The name of the input is significant obviously. The trailing “[]” on the name means the end result will be the list of checked ids. This list will be stored on the @params['customer'] hash with the key ‘interest_ids’. When the controller calls @customer.update_attributes(@params[:customer]), it tries to call @customer.key= for each of the keys on @params[:customer]. What’s important to realize is that these keys don’t have to actually be attributes on the Customer model. All that’s important is that there’s a key= method on the model. Model automatically contains a “collection_ids=” method for habtm and has-many associations.

This method will load the objects identified by the ids and call the “interest=(list)” method on the model with the freshly loaded list. This method in turn, will compare the list to the current list of interests and delete/add interests as necessary.

require 'csv'
   def export_to_csv@customers=CustomerInformation.find(:all)
      report = StringIO.new
      CSV::Writer.generate(report, ',') do |title|
         title << ['Id', 'Title', 'Job Title', 'First Name', 'Last Name']
         @customers.each do |c|
            title < 'text/csv; charset=iso-8859-1; header=present',:filename => 'report.csv', :disposition =>'attachment', :encoding => 'utf8')
         end
      end
   end

View:

    <% form_tag({ :action =>  :export_to_csv })do -%>
       <%= submit_tag "Export To CSV" -%>
    <% end -%>