many-to-many on a single table?

Hi,

I'm implementing a M-M relationship with a single table upon itself,
and wonder if there's anything I should look out for in rails, when
doing this. Also, what notation I would best use in Rails (I'm
guessing :through).

I'm doing this because I have a Category model, and each category
might be "similar to" a number of other categories. So, one way of
modelling this is to have a new join table with two columns which are
both Category ids.

Thanks,
Robb

Robb wrote:

Hi,

I'm implementing a M-M relationship with a single table upon itself,
and wonder if there's anything I should look out for in rails, when
doing this. Also, what notation I would best use in Rails (I'm
guessing :through).

I'm doing this because I have a Category model, and each category
might be "similar to" a number of other categories. So, one way of
modelling this is to have a new join table with two columns which are
both Category ids.

Thanks,
Robb
>

My guide may be able to help you out here:

http://frozenplague.net/2008/04/29/self-referrential-relationships/

That's excellent. Thanks!

Ryan,
I clicked your link and found a title page but no content?
Kathleen