Rails - Jul 2005 - creating a model for a join table

My project (FreeMIS) is a school MIS.  So the data contains  models for 
Pupil and Pupil_Set, with a join table that says "pupil A is in Set B"
( a
has_and_belongs_to_many relationship)

When a pupil leaves a pupil_set, I need to set the end_date column of the
join table to Time.now rather than just deleting the row in the join table.

This is proving tricky.  I can''t give the join table an id column, as
this
throws the associations, but if I don''t then I can''t create a
model for the
join table.

I guess I could fire some SQL into the system, but this seems rather ugly.

Any ideas?


Cheers,

--

Robert Jones

Robert Jones wrote:
>I can''t give the join table an id column, as this
> throws the associations, but if I don''t then I can''t
create a model for
> the join table.
Answered my own question - use set_primary_key - 

class Setlink < ActiveRecord::Base
  set_primary_key "link_id"
  belongs_to  :pupil_set
  belongs_to :pupil
end

Now it all works fine

--

Robert Jones