Dev-Feeds

This will create an array with the 10 empty elements.

>> Array.new(10, '')
Output
=> ["", "", "", "", "", "", "", "", "", ""]

To run the single migration in the db.

rake db:migrate       # Runs the full db migration
rake db:migrate VERSION=x #Runs the particular version

PostgreSQL: Reset the sequence value of the table

Result

  setval
--------
   1706
(1 row)

===============================

Example2(Recommanded)

Result

  setval
--------
   1706
(1 row)

 

===============================

PostgreSQL: Get the next sequence value of the table

select nextval('students_id_seq');

Result

 nextval
---------
    1707
(1 row)

  dERs = Student.find(:all,:select => "id", :conditions => "")
  dER_ids = dERs.map(&:id)

This updates all records that mathcing with the given conditions

 People.update_all( "name = 'Joe'", "name ilike '%joe%'" )

cookies[:login] = { :value => "asdf", :expires => Time.now + 600} 

The above cookie will :expires in 10 min .

To Delete the Cookie in Ruby on rails:

cookies.delete :login 

To Delete Cookie in Javascript:

createCookie(":login","",-1); 

Create new controller in ruby on rails is the easy thing. Just follow the following process

[root]# script/generate controller <controller-name>

Sample
script/generate controller registration

this will genereate the following folders/files.

      exists  app/controllers/
      exists  app/helpers/
      create  app/views/registration
      exists  test/functional/
      create  app/controllers/registration_controller.rb
      create  test/functional/registration_controller_test.rb
      create  app/helpers/registration_helper.rb