view db/migrate/20090312194159_add_projects_trackers_unique_index.rb @ 1087:74407a04925c issue_540

* (publication.rb) - fixed the acts_as_activity query (see diff to previous commit) - not returning duplicate results any longer; added the visible scope to the publication model;
* (init.rb) - created a new public permission - view_publication.

class AddProjectsTrackersUniqueIndex < ActiveRecord::Migration
  def self.up
    remove_duplicates
    add_index :projects_trackers, [:project_id, :tracker_id], :name => :projects_trackers_unique, :unique => true
  end

  def self.down
    remove_index :projects_trackers, :name => :projects_trackers_unique
  end

  # Removes duplicates in projects_trackers table
  def self.remove_duplicates
    Project.find(:all).each do |project|
      ids = project.trackers.collect(&:id)
      unless ids == ids.uniq
        project.trackers.clear
        project.tracker_ids = ids.uniq
      end
    end
  end
end