Add counter cache for article followers

Victor Costa
1 parent d0472735
Showing 2 changed files with 16 additions and 1 deletions Show diff stats
app/models/article_follower.rb
db/migrate/20150909091347_add_followers_count_to_article.rb
 class ArticleFollower < ActiveRecord::Base
   attr_accessible :article_id, :person_id, :since
-  belongs_to :article
+  belongs_to :article, :counter_cache => :followers_count
   belongs_to :person
 end
@@ -0,0 +1,15 @@
+class AddFollowersCountToArticle < ActiveRecord::Migration
+
+  def self.up
+    add_column :articles, :followers_count, :integer, :default => 0
+    add_column :article_versions, :followers_count, :integer
+
+    execute "update articles set followers_count = (select count(*) from article_followers where article_followers.article_id = articles.id)"
+  end
+
+  def self.down
+    remove_column :article_versions, :followers_count
+    remove_column :articles, :followers_count
+  end
+
+end
1	class ArticleFollower < ActiveRecord::Base	1	class ArticleFollower < ActiveRecord::Base
2	attr_accessible :article_id, :person_id, :since	2	attr_accessible :article_id, :person_id, :since
3	- belongs_to :article	3	+ belongs_to :article, :counter_cache => :followers_count
4	belongs_to :person	4	belongs_to :person
5	end	5	end
@@ -0,0 +1,15 @@		@@ -0,0 +1,15 @@
	1	+class AddFollowersCountToArticle < ActiveRecord::Migration
	2	+
	3	+ def self.up
	4	+ add_column :articles, :followers_count, :integer, :default => 0
	5	+ add_column :article_versions, :followers_count, :integer
	6	+
	7	+ execute "update articles set followers_count = (select count(*) from article_followers where article_followers.article_id = articles.id)"
	8	+ end
	9	+
	10	+ def self.down
	11	+ remove_column :article_versions, :followers_count
	12	+ remove_column :articles, :followers_count
	13	+ end
	14	+
	15	+end