Question

models/host.rb

class Host < ActiveRecord::Base
   has_many :report, :dependent => :delete_all
end

models/report.rb

class Report < ActiveRecord::Base
   belongs_to :host
end

Now I want to select all Hosts with their reports, including Hosts that haven’t got any report.

I tried to achieve this by

list=Host.all(:joins => "left join `reports` on reports.host_id=host.id")

but it seems like Rails only selects fields from the hosts Table. So I am not able to access the report object with list[0].report.
In addition i would be much more happy doing the select without using raw SQL commands – in a more ruby-like manner.

How to get both, the host and the report in just one select and without using SQL?

Answer 1

You can do

Host.eager_load(:reports)

Which will join the reports table and instantiated all the report objects. You can the use the loaded hosts and reports exactly as if they were being loaded on demand