Mongoid 3.x multiple database

mongoid_3_multiple_database.txt

If you want to use multiple dbs at once there are several different ways... 

1) If you want to do this on a per-model level, use .store_in (This is for all threads):

class Band
  include Mongoid::Document
  store_in database: "secondary" # This can be any name you want, no need to put it in the mongoid.yml.
end

class Artist
  include Mongoid::Document
  store_in database: "tertiary"
end

2) If you want to do this on a per-operation level, use #with (This is for current thread only):

Band.with(database: "secondary").create(...)!
band.with(database: "tertiary").update_attributes(...)

3) If you want to override this on a global level, like per-request switching, use .override_database (This is for current thread only):

Mongoid.override_database("secondary")
Band.create # Persists to secondary
band.save # Persists to secondary

I am assuming you mean in this case multiple databases in the same server or replica set...