On 14 December 2011 23:47, Peter Vandenabeele <[email protected]> wrote: > On Wed, Dec 14, 2011 at 11:12 PM, Mauro <[email protected]> wrote: >> >> I have these models: >> >> Company; >> Categories; >> Classifications. >> >> A Company has many categories and a Category has many companies. >> A Company for each of its own categories has a Classification. >> For example: >> Company-1 has Category-1 and Category-2. >> Company-1 - Category-1 has Classification-III while Company-1 - >> Category-2 has Classification IV. >> How can I declare associations? > > > Relevant documentation is here: > > http://guides.rubyonrails.org/association_basics.html > > (For similar results, google for "Rails Guides <term on interest>"). > > If I understand correctly, your case would be a perfect case for > has_many :through (and _not_ habtm) because you need > Classification attributes on each association between a > Company and a Category (then the Classification table is > the association table between Company and Category).
I'm also was thinking about has_many :through. The join model is Classification with attriìbutes like: company_id category_id classification_type classification_amount. But if classification.amount for classification.type II change I must change all the occurrences for company and categories where classification.type II occurs. I think its better to use a join table like this: company_id category_id classification_id What do you think about? -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
