Adding params field to migration file.

app/models/impression.rb

@@ -1,4 +1,2 @@
 class Impression
-  attr_accessible :params
-  store :params
 end

lib/generators/active_record/templates/create_impressions_table.rb

@@ -12,6 +12,7 @@ class CreateImpressionsTable < ActiveRecord::Migration
       t.string :session_hash
       t.text :message
       t.text :referrer
+      t.text :params
       t.timestamps
     end
     add_index :impressions, [:impressionable_type, :message, :impressionable_id], :name => "impressionable_type_message_index", :unique => false, :length => {:message => 255 }
@@ -21,6 +22,7 @@ class CreateImpressionsTable < ActiveRecord::Migration
     add_index :impressions, [:controller_name,:action_name,:request_hash], :name => "controlleraction_request_index", :unique => false
     add_index :impressions, [:controller_name,:action_name,:ip_address], :name => "controlleraction_ip_index", :unique => false
     add_index :impressions, [:controller_name,:action_name,:session_hash], :name => "controlleraction_session_index", :unique => false
+    add_index :impressions, [:impressionable_type, :impressionable_id, :params], :name => "poly_params_request_index", :unique => false
     add_index :impressions, :user_id
   end
 

lib/impressionist/models/active_record/impression.rb

@@ -9,6 +9,6 @@ class Impression < ActiveRecord::Base
   # sets belongs_to and attr_accessible depending on Rails version
   Impressionist::SetupAssociation.new(self).set
 
+  store :params
   after_save :impressionable_counter_cache_updatable?
-
 end

lib/impressionist/setup_association.rb

@@ -35,7 +35,8 @@ module Impressionist
                         :view_name,
                         :referrer,
                         :message,
-                        :user_id)
+                        :user_id,
+                        :params)
       end
 
       def toggle