Rails - May 2006 - has_many :through with a polymorphic join

Hi,
Four tables: users, user_counties, uk_counties and us_counties.

Each user has many counties, and each county has many users, so I
decided to make user_counties a polymorph, so it can have counties
from different countries (each country requires a completely different
set of tables with a completely different set of properties, that''s
why there''s one table for uk_counties and one for us_counties, with
more to follow when more countries are supported). This would require:

class User...
  has_many :counties, :through => user_counties #counties is the imaginary
table
end

class UserCounties
   belongs_to :counties, :polymorphic => true
end

Is this possible? If not, can anyone think of a way around it other
than adding another table into the chain? And (bonus question... not
required, just for fun) what would the reverse relationship look like
(ie, how would uk_counties relate to users)?
-Nathan

unknown wrote:
> Four tables: users, user_counties, uk_counties and us_counties.
> 
> Each user has many counties, and each county has many users, so I
> decided to make user_counties a polymorph...
http://blog.hasmanythrough.com/articles/2006/04/03/polymorphic-through

--
Josh Susser
http://blog.hasmanythrough.com

-- 
Posted via http://www.ruby-forum.com/.

Ah, thanks Josh. Nice to see that you''d already written an in-depth
answer to my problem.
-N

On 22/05/06, Josh Susser <josh@hasmanythrough.com>
wrote:
> unknown wrote:
> > Four tables: users, user_counties, uk_counties and us_counties.
> >
> > Each user has many counties, and each county has many users, so I
> > decided to make user_counties a polymorph...
>
> http://blog.hasmanythrough.com/articles/2006/04/03/polymorphic-through
>
> --
> Josh Susser
> http://blog.hasmanythrough.com
>
> --
> Posted via http://www.ruby-forum.com/.
> _______________________________________________
> Rails mailing list
> Rails@lists.rubyonrails.org
> http://lists.rubyonrails.org/mailman/listinfo/rails
>

unknown wrote:
> Ah, thanks Josh. Nice to see that you''d already written an
in-depth
> answer to my problem.
About half the reason I keep the blog is to avoid having to repeat 
myself :-)
Glad you found it useful!

--
Josh Susser
http://blog.hasmanythrough.com

-- 
Posted via http://www.ruby-forum.com/.