Issue w/ Eager Loading


I have a rails app that uses these models:

class CoreRouter < ActiveRecord::Base
has_many :ports

class Port < ActiveRecord::Base
belongs_to :core_router
has_many :addresses

class Address < ActiveRecord::Base
belongs_to :port

I have one main list page that shows all CoreRouters, the associated
ports and the associated addresses. The problem is that I now have over
400 addresses and I'm seeing over 400 queries when I generate this page,
taking about 10 seconds to load. I thought an answer may be Eager

@core_routers = CoreRouter.find(:all, :include => [ :ports, :addresses

But that fails:

ActiveRecord::ConfigurationError (Association named 'addresses' was not
found; perhaps you misspelled it?):

I'm assuming this is because the CoreRouter class doesn't have a direct
association with the Address class.

How can I get it to eagerly load the addresses that are associated with
the ports?

@core_routers = CoreRouter.find(:all,
:include => {:ports => :addresses})

(it's either that or...)

:include => :ports => :addresses)

I can never remember as well I've never actually done it :slight_smile:

Yeah, it's that.

and if you need to include a :conditions option when you have :include's, you need to indicate the table such as
:conditions => [ 'core_routers.installed_on < ? AND ports.in_use = ?',
                  1.year.ago.beginning_of_day.to_s(:db), true ]


Rob Biedenharn