demo_app/my_platform/db/migrate/20150325105880_create_last_seen_activities.your_platform.rb
# This migration comes from your_platform (originally 20140808223512)
class CreateLastSeenActivities < ActiveRecord::Migration[4.2]
def change
create_table :last_seen_activities do |t|
t.integer :user_id
t.string :description
t.integer :link_to_object_id
t.string :link_to_object_type
t.timestamps
end
end
end