named_scope not retrieving id

Hi all,

I was having a problem with a named_scope and wondered if anyone else
had the same problem before and if there was a way to keep the
named_scope and work around this. I had the following code in a
Student model:

named_scope :preceptorless, :conditions =>
[ "preceptor_students.preceptor_id IS NULL" ], :joins => "LEFT OUTER
JOIN preceptor_students ON preceptor_students.student_id =
students.id" }

I then referred to it without additional arguments. It would
successfully return the records, but without an ID for each. I then
changed it to the following code:

  def self.preceptorless(*args)
    with_scope(:find =>
                { :conditions => [ "preceptor_students.preceptor_id IS
NULL" ], :joins => "LEFT OUTER JOIN preceptor_students ON
preceptor_students.student_id = students.id" }) do
      find(*args)
    end
  end

I then referred to it as Student.preceptorless(:all). It would then
return the same records, but WITH an ID for the student.

Is there some documentation I am missing as to why the named_scope did
not return the ID of each student with the rest of the record? I'd
love to keep this as a named_scope since it reads a bit better in my
opinion, but I need the IDs to populate javascript code in a view. I
even tried on each specifying the :select and it still would return
nil for the ID.

To clarify the models, I have a Preceptor model, a Student model, and
a many-to-many relationship with extra data named PreceptorStudent.

If anyone can shed some light on this, I'd greatly appreciate it. I'm
going to continue to look into why this was the case, but at the
moment, I am at a loss.

Thanks for your views and help,
  Dave

Any ideas?

Hi all,

I was having a problem with a named_scope and wondered if anyone else
had the same problem before and if there was a way to keep the
named_scope and work around this. I had the following code in a
Student model:

you should add a :select or else the id from the table you join could
squash the original id. You said you tried adding a :select clause -
what was it ?

Fred

Hi Fred,

I included things like the id and the first and last name. I also was
specific on the table to pull from (table.field). Even when I
specifically selected the id, it turned up nil, so I'm not sure.

Dave