class Person < ActiveRecord::Base
  establish_connection(:hr)
end

class Ticket < ActiveRecord::Base
  establish_connection(:bug_tracker)
end

class HR < ActiveRecord::Base
  establish_connection(:hr)
end

class People < HR
  # ...
end

class Resource < HR
  # ...
end

4 Responses to “Connecting to Multiple Databases Using ActiveRecord”

1. mlambie Says:
   October 30th, 2009 at 5:00 pm

   Very cool Radar. I especially like extending AR::Base.

2. almost effortless » Weekly Digest, 11-6-09 Says:
   November 7th, 2009 at 6:57 am

   [...] Connecting to Multiple Databases Using ActiveRecord You can call establish_connection with the key that points to another database config in your config/database.yml file [...]

3. AL Says:
   November 10th, 2009 at 7:11 am

   Good tip. I was able to use establish_connection on the model class, but when I tried to use the extension example:

   class MCK < ActiveRecord::Base establish_connection(:Mydb) end

   class Mckuser < MCK end

   I get an error:

   Table ‘Mydb.mcks’ doesn’t exist: SHOW FIELDS FROM mcks

   I place the mck.rb file on the lib folder.Any help would be appreciated

4. Nathan Zook Says:
   February 20th, 2010 at 5:25 am

   AL: Here’s what you need: class HR < ActiveRecord::Base @abstractclass = true establishconnection(:hr) end

   My current employer is using four databases (on two servers). I do the following: class ApplicationModel < ActiveRecord::Base @abstract_class = true

   def self.setupconnection basename = self.name.sub(/ConnectBase$/, ”) establishconnection(ActiveRecord::Base.configurations["#{basename.underscore}#{RAILSENV}"]) end end

   class MyDBConnectBase < ApplicationModel

   @abstractclass = true setupconnection

   end

   Then all of my models inherit from one of the MyDBConnectBases.

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