That's in ActiveRecord 4.0 as well! https://github.com/rails/rails/pull/4775 https://github.com/rails/rails/pull/4775 Take a look at @tenderlove's comment dow

That's in ActiveRecord 4.0 as well! https://github.com/rails/rails/pull/4775 https://github.com/rails/rails/pull/4775 Take a look at @tenderlove's comment down below about the actual implementation (as opposed to my crappy one in the issue body).