README.md in disco-0.1.3 vs README.md in disco-0.2.0

@@ -99,17 +99,17 @@
 [Ahoy](https://github.com/ankane/ahoy) is a great source for implicit feedback
 
 ```ruby
 views = Ahoy::Event.
   where(name: "Viewed post").
-  group(:user_id, "properties->>'post_id'") # postgres syntax
+  group(:user_id, "properties->>'post_id'"). # postgres syntax
   count
 
 data =
   views.map do |(user_id, post_id), count|
     {
       user_id: user_id,
-      post_id: post_id,
+      item_id: post_id,
       value: count
     }
   end
 ```