Rails - Jul 2006 - conditional table association?

I''m using a db to log two types of events, link events and tag  
events. At first I had two tables, link_events & tag_events, but this  
seemed not very DRY because the only column that was different  
between them was link_id and tag_id respectively. So I made these  
tables:

events:
id			int
user_id		int
objtype_id	int (holds ''1'' or ''2'' depending
on if the item is a link
or a tag)
lort_id		int ("link or tag id" == "lort" this holds the id
of the
item involved in the event)

objtypes: (only has two records {1 => link, 2 => tag})
id		int	
name 	int

links:
id		int
url		string

tags:
id		int
name	string

What I can''t figure out is how to tell the Event model that lort_id  
belongs_to links if the value is 1, and that it belongs_to tags if  
the value is 2. Is this possible/wise/insane?

Thanks in advance!
-Jason
--
Jason Frankovitz - jason@seethroo.us - http://www.seethroo.us/
work: (310) 601-8454
cell: (415) 254-4890
AIM/Skype: jfrankov

-------------- next part --------------
An HTML attachment was scrubbed...
URL:
http://wrath.rubyonrails.org/pipermail/rails/attachments/20060708/2065746a/attachment.html

You''re on the right track.  Look at the polymorphic associations  
described in:  http://api.rubyonrails.org/classes/ActiveRecord/ 
Associations/ClassMethods.html

It was something like this that I figured out how to do in 1.0 about  
a week before 1.1 introduced polymorphic associations.

-Rob


Rob Biedenharn		http://agileconsultingllc.com
Rob@AgileConsultingLLC.com


On Jul 7, 2006, at 8:33 PM, Jason Frankovitz wrote:
> I''m using a db to log two types of events, link events and tag  
> events. At first I had two tables, link_events & tag_events, but  
> this seemed not very DRY because the only column that was different  
> between them was link_id and tag_id respectively. So I made these  
> tables:
>
> events:
> id			int
> user_id		int
> objtype_id	int (holds ''1'' or ''2''
depending on if the item is a link
> or a tag)
> lort_id		int ("link or tag id" == "lort" this holds the
id of the
> item involved in the event)
>
> objtypes: (only has two records {1 => link, 2 => tag})
> id		int	
> name 	int
>
> links:
> id		int
> url		string
>
> tags:
> id		int
> name	string
>
> What I can''t figure out is how to tell the Event model that
lort_id
> belongs_to links if the value is 1, and that it belongs_to tags if  
> the value is 2. Is this possible/wise/insane?
>
> Thanks in advance!
> -Jason
> --
> Jason Frankovitz - jason@seethroo.us - http://www.seethroo.us/
> work: (310) 601-8454
> cell: (415) 254-4890
> AIM/Skype: jfrankov
>
> _______________________________________________
> Rails mailing list
> Rails@lists.rubyonrails.org
> http://lists.rubyonrails.org/mailman/listinfo/rails
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
http://wrath.rubyonrails.org/pipermail/rails/attachments/20060708/90977950/attachment.html