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copied!<p>I've come across this data problem several times and have tried a few different strategies. I think the one I'm a biggest fan of, is the STI approach as mentioned by cicloon. Make sure you have a <code>type</code> column on your entry table.</p> <pre><code>class Blog < ActiveRecord::Base # this is your generic association that would return all types of entries has_many :entries # you can also add other associations specific to each type. # through STI, rails is aware that a media_entry is in fact an Entry # and will do most of the work for you. These will automatically do what cicloon. # did manually via his methods. has_many :articles has_many :quotes has_many :media end class Entry < ActiveRecord::Base end class Article < Entry has_one :article_data end class Quote < Entry has_one :quote_data end class Media < Entry has_one :media_data end class ArticleData < ActiveRecord::Base belongs_to :article # smart enough to know this is actually an entry end class QuoteData < ActiveRecord::Base belongs_to :quote end class MediaData < ActiveRecord::Base belongs_to :media end </code></pre> <p>The thing I like about this approach, is you can keep the generic Entry data in the entry model. Abstract out any of the sub-entry type data into their own data tables, and have a has_one association to them, resulting in no extra columns on your entries table. It also works very well for when you're doing your views:</p> <pre><code>app/views/articles/_article.html.erb app/views/quotes/_quote.html.erb app/views/media/_media.html.erb # may be medium here.... </code></pre> <p>and from your views you can do either:</p> <pre><code><%= render @blog.entries %>  </code></pre> <p>or have more control:</p> <pre><code><%= render @blog.quotes %> <%= render @blog.articles %> </code></pre> <p>You can find a pretty generic way of generating forms as well, I usually render the generic entry fields in an <code>entries/_form.html.erb</code> partial. Inside that partial, I also have a</p> <pre><code><%= form_for @entry do |f| %> <%= render :partial => "#{f.object.class.name.tableize}/#{f.object.class.name.underscore}_form", :object => f %> <% end %> </code></pre> <p>type render for the sub form data. The sub forms in turn can use <code>accepts_nested_attributes_for</code> + <code>fields_for</code> to get the data passed through properly.</p> <p>The only pain I have with this approach, is how to handle the controllers and route helpers. Since each entry is of its own type, you'll either have to create custom controllers / routes for each type (you may want this...) or make a generic one. If you take the generic approach, two things to remember. </p> <p>1) You can't set a <code>:type</code> field through update attributes, your controller will have to instantiate the appropriate <code>Article.new</code> to save it (you may use a factory here). </p> <p>2) You'll have to use the <code>becomes()</code> method (<code>@article.becomes(Entry)</code>) to work with the entry as an Entry and not a subclass.</p> <p>Hope this helps.</p> <p><strong>Warning, I've actually used Media as a model name in the past. In my case it resulted in a table called medias in rails 2.3.x however in rails 3, it wanted my model to be named Medium and my table media. You may have to add a custom Inflection on this naming, though I'm not sure.</strong></p>

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