Migrations iproved

db/migrate/20130218141258_convert_closed_to_state_in_issue.rb

 class ConvertClosedToStateInIssue < ActiveRecord::Migration
   def up
     Issue.transaction do
-      Issue.find_each do |issue|
-        issue.state = issue.closed? ? :closed : :opened
-        issue.save
-      end
+      Issue.where(closed: true).update_all("state = 'closed'")
+      Issue.where(closed: false).update_all("state = 'opened'")
     end
   end
 
   def down
     Issue.transaction do
-      Issue.find_each do |issue|
-        issue.closed = issue.closed?
-        issue.save
-      end
+      Issue.where(state: :closed).update_all("closed = 1")
     end
   end
 end

db/migrate/20130218141327_convert_closed_to_state_in_merge_request.rb

 class ConvertClosedToStateInMergeRequest < ActiveRecord::Migration
   def up
     MergeRequest.transaction do
-      MergeRequest.find_each do |mr|
-        if mr.closed? && mr.merged?
-          mr.state = :merged
-        else 
-          if mr.closed? 
-            mr.state = :closed
-          else 
-            mr.state = :opened
-          end
-        end
-
-        mr.save
-      end
+      MergeRequest.where("closed = 1 AND merged = 1").update_all("state = 'merged'")
+      MergeRequest.where("closed = 1 AND merged = 0").update_all("state = 'closed'")
+      MergeRequest.where("closed = 0").update_all("state = 'opened'")
     end
   end
 
   def down
     MergeRequest.transaction do
-      MergeRequest.find_each do |mr|
-        mr.closed = mr.closed? || mr.merged?
-        mr.closed = mr.merged?
-        mr.save
-      end
+      MergeRequest.where(state: :closed).update_all("closed = 1")
+      MergeRequest.where(state: :merged).update_all("closed = 1, merged = 1")
     end
   end
 end

db/migrate/20130218141344_convert_closed_to_state_in_milestone.rb

 class ConvertClosedToStateInMilestone < ActiveRecord::Migration
   def up
     Milestone.transaction do
-      Milestone.find_each do |milestone|
-        milestone.state = milestone.closed? ? :closed : :active
-        milestone.save
-      end
+      Milestone.where(closed: false).update_all("state = 'opened'")
+      Milestone.where(closed: false).update_all("state = 'active'")
     end
   end
 
   def down
     Milestone.transaction do
-      Milestone.find_each do |milestone|
-        milestone.closed = milestone.closed?
-        milestone.save
-      end
+      Milestone.where(state: :closed).update_all("closed = 1")
     end
   end
 end