This gem doesn’t really work on Rails 4 – no plans on upgrading it anyway. you probably should take a look at lol_dba

Rails indexes is a small package of 2 rake tasks that scan your application models and displays a list of columns that probably should be indexed.

Note: there may be more fields depending on your application design and custom queries.

If you’re using Rails 3.x or 4.x, you probably should take a look at lol_dba

as a rails plugin:

script/plugin install git://github.com/eladmeidar/rails_indexes.git

Display a migration for adding/removing all necessary indexes based on associations:

rake db:index_migration

Display a migration for adding/removing all necessary indexes based on AR::Base#find calls (including: find, find_by, find_all_by, find_by_x_and_y, find_all_by_x_and_y):

rake db:find_query_indexes

Note that it would probably make more sense running those tasks on production, where you actually need those indexes to be added.

Requires SQLite3 installed, then just:

rake

Elad Meidar – http://blog.eizesus.com

Thanks:
Eric Davis – http://littlestreamsoftware.com

Released under the same license as Ruby. No Support. No Warranty, no Pain.