possible bug: belongs_to with :class_name and eager loading

rubyonrails-talk
1

In my model: class Call < ActiveRecord::Base   belongs_to :doctor, :class_name => 'User' end

In the migration:   t.column :doctor_id, :int

call.doctor.last_name works great. But my view had an N+1 problem. So I modified my find to this:

@calls = Call.find(:all, :conditions => { :day => (d-1.day)..d.end_of_month }, :include => [:doctor])

Suddenly my code blew up with an SQL error. The SQL contained `calls`.user_id instead of `calls`.doctor_id. I found the fragment of code causing the error. In Rails 2.0.2, this is lines 1704-1711 of active_record/associations.rb:

              when :belongs_to                   " #{join_type} %s ON %s.%s = %s.%s " % [                      table_name_and_alias,          connection.quote_table_name(aliased_table_name),          reflection.klass.primary_key,

connection.quote_table_name(parent.aliased_table_name),          options[:foreign_key] || klass.to_s.foreign_key                     ]

I worked around this possible bug by changing my model code to:

  belongs_to :doctor, :class_name => 'User', :foreign_key => 'doctor_id'

It seems I shouldn't have to do that. Is this a bug?

thanks, Bryan

2

In my model: class Call < ActiveRecord::Base belongs_to :doctor, :class_name => 'User' end

In the migration: t.column :doctor_id, :int

call.doctor.last_name works great. But my view had an N+1 problem. So I modified my find to this:

@calls = Call.find(:all, :conditions => { :day => (d-1.day)..d.end_of_month }, :include => [:doctor])

Suddenly my code blew up with an SQL error. The SQL contained `calls`.user_id instead of `calls`.doctor_id. I found the fragment of code causing the error. In Rails 2.0.2, this is lines 1704-1711 of active_record/associations.rb:

THis appears relevant: http://dev.rubyonrails.org/changeset/8456 Looks like this was a bug and it has been fixed Fred