# HABTM vs. using has\_many :through **URL:** \ **Category:** Rails\ **Created:** [July 10, 2006, 9:25am UTC](https://www.ruby-forum.com/t/habtm-vs-using-has-many-through/97744 "2006-07-10T09:25:41Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![weyus](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/w/7ab992/32.png) [@weyus](https://www.ruby-forum.com/u/weyus)\ **Post date:** [July 10, 2006, 9:25am UTC](https://www.ruby-forum.com/t/habtm-vs-using-has-many-through/97744/1 "2006-07-10T09:25:41Z")
All, I’ve heard recently about has\_many :through as a necessary alternative to HABTM (when the join table has it’s own id column, say, in a legacy schema). However, is the prevailing Rails wisdom now that one should use has\_many :through in _all_ cases? If so, why? Thanks, Wes ---
**Author:** ![weyus](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/w/7ab992/32.png) [@weyus](https://www.ruby-forum.com/u/weyus)\ **Post date:** [July 10, 2006, 10:03am UTC](https://www.ruby-forum.com/t/habtm-vs-using-has-many-through/97744/2 "2006-07-10T10:03:46Z")
Uber associationatire Josh S. has written a much recommended article outlining the features and pros/cons of habtm and hmt: [http://blog.hasmanythrough.com/articles/2006/04/20/many-to-many-dance-off](http://blog.hasmanythrough.com/articles/2006/04/20/many-to-many-dance-off). > However, is the prevailing Rails wisdom now that one should > use has\_many :through in _all_ cases? > As with a lot of Rails wisdom the short answer is ‘it depends’ :0) Steve ---
**Author:** ![weyus](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/w/7ab992/32.png) [@weyus](https://www.ruby-forum.com/u/weyus)\ **Post date:** [July 11, 2006, 2:33am UTC](https://www.ruby-forum.com/t/habtm-vs-using-has-many-through/97744/3 "2006-07-11T02:33:05Z")
It may be heresy to some, but I still prefer HABTM over has\_many :through if the relationship I’m dealing with is simple. i.e., if there’s no reason to store any metainfo in a join model, I just use HABTM. I like my proxy collections! This doesn’t mean I don’t love (and use) has\_many :through for situations when there does need to be metainfo stored about the relationship. But I always ask myself first before I decide which to use. -Seth ---
**Author:** ![weyus](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/w/7ab992/32.png) [@weyus](https://www.ruby-forum.com/u/weyus)\ **Post date:** [July 11, 2006, 2:42am UTC](https://www.ruby-forum.com/t/habtm-vs-using-has-many-through/97744/4 "2006-07-11T02:42:49Z")
Agreed. ---
**Author:** ![weyus](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/w/7ab992/32.png) [@weyus](https://www.ruby-forum.com/u/weyus)\ **Post date:** [July 11, 2006, 10:05am UTC](https://www.ruby-forum.com/t/habtm-vs-using-has-many-through/97744/5 "2006-07-11T10:05:43Z")
Wes G. wrote: > All, > > I’ve heard recently about has\_many :through as a necessary alternative > to HABTM (when the join table has it’s own id column, say, in a legacy > schema). However, is the prevailing Rails wisdom now that one should > use has\_many :through in _all_ cases? Not at all. Think about the model first. Do you want to model your associations explicitly, using a model class? In other words, are there things that you want to say about the associations? (Can you put a name to them? This may help you to find things that you might want to say about them.) If so, use a model for the association… and then you will need the :through capability to let you navigate through the association in a single query. If you just want the association to exist, with nothing further being said about it, stick with HABTM. In other words, I agree with others in this thread, but would like to put the emphasis on thinking carefully about the domain model. regards Justin