FEATURE: remove star concept from Discourse

db/migrate/20150106215342_remove_stars.rb

@@ -0,0 +1,29 @@
+class RemoveStars < ActiveRecord::Migration
+  def up
+    r = execute <<SQL
+    INSERT INTO post_actions(user_id, post_id, post_action_type_id, created_at, updated_at)
+    SELECT tu.user_id, p.id, 1, coalesce(tu.starred_at, now()), coalesce(tu.starred_at, now())
+    FROM topic_users tu
+    JOIN posts p ON p.topic_id = tu.topic_id AND p.post_number = 1
+    LEFT JOIN post_actions pa ON
+        pa.post_id = p.id AND
+        pa.user_id = tu.user_id AND
+        pa.post_action_type_id = 1
+    WHERE pa.post_id IS NULL AND tu.starred
+SQL
+   puts "#{r.cmd_tuples} stars were converted to bookmarks!"
+
+   execute <<SQL
+   DELETE FROM user_actions WHERE action_type = 10
+SQL
+
+    remove_column :topic_users, :starred
+    remove_column :topic_users, :starred_at
+    remove_column :topic_users, :unstarred_at
+    remove_column :topics, :star_count
+  end
+
+  def down
+    raise ActiveRecord::IrreversibleMigration
+  end
+end