example usage

# Attach the scope as part of a chain in an ActiveRecord query:
UserFacebookFanpages.valid.tracked.find(:all)

model

class UserFacebookFanpages < ActiveRecord::Base  
  # ...

  # Scopes
  scope :valid, where("is_invalid != null OR is_invalid != 0")
  scope :invalid, where(:is_invalid => true)
  scope :tracked, where(:is_tracked => true)
  scope :not_tracked, where(:is_tracked => false)

  #...
end