heroku rake db:migrate aborting

heroku rake db:migrate
rake aborted!
no such file to load -- acts_as_ferret

(See full trace by running tas开发者_JAVA技巧k with --trace)
(in /disk1/home/slugs/310513_b4b7e61_4c01/mnt)

It show this message issue. how do I fixes this?

1. add gem in your gem file "acts_as_ferret"
2. bundle install
3. run heroku run rake db:migrate

Add the gem act_as_ferret gem.

But seems complicated in heroku environement without ferret.