How to mix mongodb and a traditional db in Rails?

Question

I am considering using MongoDB (mongo-mapper) for a portion of my rails application. I am not ready to go whole hog MongoDB because there are too many useful gems that depend on a traditional DB.

That being said there are parts of my application that would be great to leverage a document database.

Has anyone had success mixing the two approaches? How do you link activerecord models with mongomapper models?

Thanks,

Jonathan

Answer 1

MongoMapper doesn't implement ActiveModel yet, but I think there are a few forks on github that do. You could use Mongoid instead (which does) and your relationships between Mongoid docs and ActiveRecord entries would just magically work. I know a number of people are doing that.

That said, I wouldn't want to mix them unless I absolutely had to have an RDBMS for some reason.

Answer 2

http://railscasts.com/episodes/194-mongodb-and-mongomapper http://www.mongodb.org/display/DOCS/Object+Mappers+for+Ruby+and+MongoDB http://www.mongodb.org/display/DOCS/MongoDB+Data+Modeling+and+Rails http://www.mongodb.org/display/DOCS/Ruby+Language+Center

You need to mixin mongomapper with the model class This gives you freedom to define the key-value pairs other than activerecord

include MongoMapper::Document

Dead simple I think.

Answer 3

Here a presentation about this issue: http://nosql.mypopescu.com/post/541657350/presentation-blending-nosql-and-sql-at-confoo

I don't know ROR so I can't judge it is a good presentation.