在rails中从MongoDB迁移回ActiveRecord

Question

When I migrated my MongoDB database back to a simple SQL database, I received some errors, mainly:

uninitialized constant BSON [NameError]

and

Cannot visit BSON::ObjectId

I followed this guide to perform my migration.

Any clue?

-frbl

Answer 1

It took me some hours to figure out, but it seemed to be extremely simple. These are all steps I took. Note that this application did not contain any valuable information, so destroying everything was not an issue for me.

Remove all devise stuff (model, initializer, routes and views like described here Set the basic ORM models back to ActiveModels:

code:

config.generators do |g|
   g.orm :active_record
end

Re-install devise:

rails g devise:install
rails g devise user
rake db:migrate

now everything is set up, but the most important point, remove your session!! What I dit was changing the secret code in config/initializers/secret_token.rb (according to this guide)

Took me 3 hours, so I hope it saves you some time.

-frbl