Update join_table attributes


#1

I have two ActiveRecord classes that point at each other with a
“has_and_belongs_to_many” (habtm) relationship using a join table. The
join
table has an a few additional columns besides the _id columns.

For those of you with the Agile Web Dev w/ Rails book, it’s exactly the
same
setup as the articles<->articles_users<->users example on p240.

The habtm relationship is setup fine. I can see the linked data in
instances of the objects.

The problem, though, is that I can’t update the extra columns in the
join
table using update_attributes. This is a well documented shortcoming,
and
the solution everyone talks about is to override the update_attributes
code.

The code (see the comments @ http://tinyurl.com/ey5qd) starts like so:

module ActiveRecord
module Associations
class HasAndBelongsToManyAssociation
def update_attributes(record, join_attributes = {})

The problem is, and here is why I’m writing, that this code isn’t called
when you call update_attributes. In fact, if you go and edit the file
that
defines HasAndBelongsToManyAssociations and you put in a method “foo”
and
call it, it won’t be called either.

Would be grateful for any assistance.


#2

http://www.matthewman.net/articles/2006/01/06/rails-activerecord-goes-through


#3

Why not use edge rails :though?