Adds a branch for unlimited project hierarchy.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/branches/work@2148 e93f8b46-1217-0410-a6f0-8f06a7374b81

nested_projects/db/migrate/081_create_projects_trackers.rb

@@ -0,0 +1,19 @@
+class CreateProjectsTrackers < ActiveRecord::Migration
+  def self.up
+    create_table :projects_trackers, :id => false do |t|
+      t.column :project_id, :integer, :default => 0, :null => false
+      t.column :tracker_id, :integer, :default => 0, :null => false
+    end
+    add_index :projects_trackers, :project_id, :name => :projects_trackers_project_id
+    
+    # Associates all trackers to all projects (as it was before)
+    tracker_ids = Tracker.find(:all).collect(&:id)
+    Project.find(:all).each do |project|
+      project.tracker_ids = tracker_ids
+    end
+  end
+
+  def self.down
+    drop_table :projects_trackers
+  end
+end