Databases
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    <p>Check out the <a href="http://en.wikipedia.org/wiki/Law_of_Demeter" rel="nofollow">Law of Demeter</a>. It explains why what you're doing is causing problems (no separation of concerns = spaghetti code). Also check out <a href="http://www.simonecarletti.com/blog/2009/12/inside-ruby-on-rails-delegate/" rel="nofollow">ActiveSupport::Delegate</a> to see how you can concisely apply the Law of Demeter to your Rails app and avoid lists of boring getters and setters.</p> <p>A few notes to help you out:</p> <ol> <li>Make all your ActiveRecord calls like <code>where</code> in your controller. Your view should have arrays (or ActiveSupport::Proxy's) to simply iterate over and display. You should avoid having your view trigger database queries, and you should never keep record-fetching business logic in them.</li> <li>Rather than chaining endlessly on your model associations, define or delegate methods from one model to another. For example, instead of <code>@comment.post.title</code>, define and use <code>@comment.post_title</code> instead (note the underscore). This avoids requiring your view to have innate knowledge of your database schema and model associations. It simply needs to know that a comment has a post title, however that data is modeled.</li> </ol> <p>If you refactor your code to keep each model focused on a single concern and modeling a single resource, then layer the associations on top of that in a clean, compartmentalized fashion, you will surely obviate the need for someone to solve this single question for you (teach a man to fish…).</p>
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    1. PORender a partial with a collection through multiple levels of has_many associations
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    1. UScoreyward
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    1. COThis is great, I'm feeling very close to a breakthrough (with some good habits to boot). Any hints on forming the query? I refactored to get @order.post_product_user_id showing up in my index (it works), but when I query Order.where(:post_product_user_id => current_user.id), I get "No attribute named `post_product_user_id` exists for table `orders`". Nothing really showed up in my research yet, but thank you for pointing me in the right direction!
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    2. COYou still are chaining through models it sounds like. In your controller action you should be handling fetching records with something like `@orders = current_user.orders`. I don't understand why you're even touching the Post or Product models to get to your user when your User and Order models are associated directly.
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    3. COI'm doing this to keep the programming DRY. The user associated with the order is the buyer, and is easily accessible. The seller is associated with the product, I don't want to repeat the seller id in the order since it is already accessable through the association. Is this an appropriate use of DRY?
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Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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