diff --git a/app/models/course_activity.rb b/app/models/course_activity.rb
index 1d0920c1c..284687870 100644
--- a/app/models/course_activity.rb
+++ b/app/models/course_activity.rb
@@ -10,7 +10,7 @@ class CourseActivity < ActiveRecord::Base
 
   #在个人动态里面增加当前动态
   def add_user_activity
-    user_activity = UserActivity.where("act_type = '#{self.class.to_s}' and act_id = '#{self.id}'").first
+    user_activity = UserActivity.where("act_type = '#{self.course_act_type.to_s}' and act_id = '#{self.course_act_id}'").first
     if user_activity
       user_activity.save
     else
@@ -24,7 +24,7 @@ class CourseActivity < ActiveRecord::Base
   end
 
   def destroy_user_activity
-    user_activity = UserActivity.where("act_type = '#{self.class.to_s}' and act_id = '#{self.id}'")
+    user_activity = UserActivity.where("act_type = '#{self.course_act_type.to_s}' and act_id = '#{self.course_act_id}'")
     user_activity.destroy_all
   end
 end
diff --git a/app/models/forge_activity.rb b/app/models/forge_activity.rb
index b7fc5e4c2..9bc10bebf 100644
--- a/app/models/forge_activity.rb
+++ b/app/models/forge_activity.rb
@@ -25,7 +25,7 @@ class ForgeActivity < ActiveRecord::Base
 
   #在个人动态里面增加当前动态
   def add_user_activity
-    user_activity = UserActivity.where("act_type = '#{self.class.to_s}' and act_id = '#{self.id}'").first
+    user_activity = UserActivity.where("act_type = '#{self.forge_act_type.to_s}' and act_id = '#{self.forge_act_id}'").first
     if user_activity
       user_activity.save
     else
@@ -39,7 +39,7 @@ class ForgeActivity < ActiveRecord::Base
   end
 
   def destroy_user_activity
-    user_activity = UserActivity.where("act_type = '#{self.class.to_s}' and act_id = '#{self.id}'")
+    user_activity = UserActivity.where("act_type = '#{self.forge_act_type.to_s}' and act_id = '#{self.forge_act_id}'")
     user_activity.destroy_all
   end
 end
diff --git a/db/migrate/20150810064247_add_created_at_to_activities.rb b/db/migrate/20150810064247_add_created_at_to_activities.rb
index 864ed82d6..e2f35441f 100644
--- a/db/migrate/20150810064247_add_created_at_to_activities.rb
+++ b/db/migrate/20150810064247_add_created_at_to_activities.rb
@@ -3,6 +3,6 @@ class AddCreatedAtToActivities < ActiveRecord::Migration
   	add_column :activities, :created_at, :timestamp
   end
   def end
-  	remove_column :activities, :created_at	
+  	remove_column :activities, :created_at
   end
 end
diff --git a/db/migrate/20150811010817_update_activities_data.rb b/db/migrate/20150811010817_update_activities_data.rb
index 7ed19a607..374407cd3 100644
--- a/db/migrate/20150811010817_update_activities_data.rb
+++ b/db/migrate/20150811010817_update_activities_data.rb
@@ -1,19 +1,19 @@
 class UpdateActivitiesData < ActiveRecord::Migration
   def up 	
-  	count = Activity.all.count / 20 + 1
-    transaction do
-      for i in 1 ... count do i
-        Activity.page(i).per(20).each do |activity|
-          type = activity.act_type
-          if type=='Contest' || type=='Message' || type=='News'|| type=='Journal'|| type=='Issue'|| type=='Principal'||type=='JournalsForMessage'
-            activity.created_at = activity.act.created_on if activity.act
-          elsif type=='Contestnotification' || type=='HomeworkCommon' || type=='Poll'
-            activity.created_at = activity.act.created_at if activity.act
-          end
-          activity.save
-	  	  end
-      end
-    end
+    # count = Activity.all.count / 20 + 1
+    # transaction do
+    #   for i in 1 ... count do i
+    #     Activity.page(i).per(20).each do |activity|
+    #       type = activity.act_type
+    #       if type=='Contest' || type=='Message' || type=='News'|| type=='Journal'|| type=='Issue'|| type=='Principal'||type=='JournalsForMessage'
+    #         activity.created_at = activity.act.created_on if activity.act
+    #       elsif type=='Contestnotification' || type=='HomeworkCommon' || type=='Poll'
+    #         activity.created_at = activity.act.created_at if activity.act
+    #       end
+    #       activity.save
+	  	#   end
+    #   end
+    # end
   end
 
   def down
diff --git a/db/migrate/20150811065543_add_course_activities.rb b/db/migrate/20150811065543_add_course_activities.rb
index 03ec7e354..86b96bd44 100644
--- a/db/migrate/20150811065543_add_course_activities.rb
+++ b/db/migrate/20150811065543_add_course_activities.rb
@@ -1,5 +1,14 @@
 class AddCourseActivities < ActiveRecord::Migration
   def up
+    create_table :user_activities do |t|
+      t.string :act_type
+      t.integer :act_id
+      t.string :container_type
+      t.integer :container_id
+
+      t.timestamps
+    end
+
     create_table :course_activities do |t|
       t.integer :user_id
       t.integer :course_id
@@ -11,5 +20,6 @@ class AddCourseActivities < ActiveRecord::Migration
 
   def down
     drop_table :course_activities
+    drop_table :user_activities
   end
 end
diff --git a/db/migrate/20150811080754_course_activities.rb b/db/migrate/20150811080754_course_activities.rb
index a4cae915d..910cb4520 100644
--- a/db/migrate/20150811080754_course_activities.rb
+++ b/db/migrate/20150811080754_course_activities.rb
@@ -35,6 +35,6 @@ class CourseActivities < ActiveRecord::Migration
   end
 
   def down
-    CourseActivity.destroy_all
+    # CourseActivity.destroy_all
   end
 end
diff --git a/db/migrate/20150814031258_update_course_activity_time.rb b/db/migrate/20150814031258_update_course_activity_time.rb
index 155e212a3..26d0dc4bc 100644
--- a/db/migrate/20150814031258_update_course_activity_time.rb
+++ b/db/migrate/20150814031258_update_course_activity_time.rb
@@ -1,9 +1,9 @@
 class UpdateCourseActivityTime < ActiveRecord::Migration
   def up
-    count = CourseActivity.all.count / 10 + 1
+    count = CourseActivity.all.count / 30 + 1
     transaction do
       for i in 1 ... count do i
-      CourseActivity.page(i).per(10).each do |activity|
+      CourseActivity.page(i).per(30).each do |activity|
         if activity.course_act
           if activity.course_act.respond_to?("created_at")
             activity.created_at = activity.course_act.created_at
@@ -11,6 +11,10 @@ class UpdateCourseActivityTime < ActiveRecord::Migration
             activity.created_at = activity.course_act.created_on
           end
           activity.save
+
+          user_activity = UserActivity.where("act_type = '#{activity.course_act_type.to_s}' and act_id = '#{activity.course_act_id}'").first
+          user_activity.created_at = activity.created_at
+          user_activity.save
         end
       end
       end
diff --git a/db/migrate/20150820022416_create_user_activity.rb b/db/migrate/20150820022416_create_user_activity.rb
index 7d6a978d1..0ff64b1f3 100644
--- a/db/migrate/20150820022416_create_user_activity.rb
+++ b/db/migrate/20150820022416_create_user_activity.rb
@@ -1,16 +1,9 @@
 class CreateUserActivity < ActiveRecord::Migration
   def up
-    create_table :user_activities do |t|
-      t.string :act_type
-      t.integer :act_id
-      t.string :container_type
-      t.integer :container_id
 
-      t.timestamps
-    end
   end
 
   def down
-    drop_table :user_activities
+
   end
 end
diff --git a/db/migrate/20150820025358_about_user_activities.rb b/db/migrate/20150820025358_about_user_activities.rb
index 82b58a537..e02b4711f 100644
--- a/db/migrate/20150820025358_about_user_activities.rb
+++ b/db/migrate/20150820025358_about_user_activities.rb
@@ -15,23 +15,23 @@ class AboutUserActivities < ActiveRecord::Migration
       end
     end
 
-    course_count = CourseActivity.all.count / 30 + 2
-    transaction do
-      for i in 1 ... course_count do i
-      CourseActivity.page(i).per(30).each do |activity|
-        user_activity = UserActivity.new
-        user_activity.act_id = activity.course_act_id
-        user_activity.act_type = activity.course_act_type
-        user_activity.container_type = "Course"
-        user_activity.container_id = activity.course_id
-        user_activity.created_at = activity.created_at
-        user_activity.save
-      end
-      end
-    end
+    # course_count = CourseActivity.all.count / 30 + 2
+    # transaction do
+    #   for i in 1 ... course_count do i
+    #   CourseActivity.page(i).per(30).each do |activity|
+    #     user_activity = UserActivity.new
+    #     user_activity.act_id = activity.course_act_id
+    #     user_activity.act_type = activity.course_act_type
+    #     user_activity.container_type = "Course"
+    #     user_activity.container_id = activity.course_id
+    #     user_activity.created_at = activity.created_at
+    #     user_activity.save
+    #   end
+    #   end
+    # end
   end
 
   def down
-    UserActivity.destroy_all
+    # UserActivity.destroy_all
   end
 end
diff --git a/db/schema.rb b/db/schema.rb
index 5b09c8f3d..3c43292e5 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -913,7 +913,6 @@ ActiveRecord::Schema.define(:version => 20150826061843) do
     t.datetime "created_on"
     t.integer  "comments_count",               :default => 0,  :null => false
     t.integer  "course_id"
-    t.datetime "updated_on"
   end
 
   add_index "news", ["author_id"], :name => "index_news_on_author_id"