If you just want to create a join table then,
1. Remove the existing migration
rails d migration UserRolesJoin
2. Create a new migration for join table as
rails g migration CreateJoinTableUserRole user role
This will create a migration like:
class CreateJoinTableUserRole < ActiveRecord::Migration
def change
create_join_table :users, :roles do |t|
# t.index [:user_id, :role_id]
# t.index [:role_id, :user_id]
end
end
end
NOTE: You need to uncomment one of the combination as per your requirement from the generated migration.
3. Run rake db:migrate