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+---
+layout: post
+title: Same class associations in Rails 3
+tags: development
+type: post
+published: true
+---
+
+**[TL;DR]** Even though the selected events conceptually belong to a record,
+the latter has the foreign keys to former. So technically, `has_one`
+is to be changed to `belongs_to`.
+
+* * *
+
+This is the first time I've ran into something like this and it was interesting
+to realize what it actually means when developing a business logic in Rails.
+
+### Context
+
+In this app I'm building, I have <em>Students</em> that have a <em>Record</em>
+per year. Each record has several <em>Events</em>. These records also have two
+specific events: a <em>test</em> and an <em>audition</em>, registered in the
+schema as `id`'s in the record's table.
+
+### So what did technically happen?
+
+I wasn't able to access those specific events through the associations
+specified in the model. Given <code>r = Record.first</code>, when I tried to
+access the audition, by using <code>r.test</code>, Rails would use a SQL query
+that would correspond to <code>r.events.first</code> instead.
+
+After acknowledging that, I turned to <a
+href="http://twitter.com/varandas">@varandas</a> and we both thought it might
+be a bug in the Rails framework. Turns out it wasn't; all I had to do was
+switch from <code>has\_one</code> to <code>belongs\_to</code> (thanks <a
+  href="http://github.com/drogus">@drogus</a>!). The reason for that is the
+  foreign key is on the <code>records</code> table. From the framework's
+  perspective, it looks like the record actually <em>belongs to</em> the event,
+  when in practice it's not.
+
+### Code sample
+
+<script src="http://gist.github.com/1449428.js"></script>