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    <p>The migration has no knowledge of how you intend to use the tables defined within it. All that information goes in the models.</p> <p>In short your migration is fine for what you've described will be done. But you need to flesh out the models to define the associations you're thinking of.</p> <pre><code>class Comic &lt; ActiveRecord::Base belongs_to :writer, :class_name =&gt; "Person" belongs_to :artist, :class_name =&gt; "Person" end </code></pre> <p>This allows you to reference the Writer and Artist from a Comic. However, you will probably want to reciprocate the association so that you can easily fetch a comic from a person based on their role in it's production.</p> <pre><code>class Person &lt; ActiveRecord::Base has_many :comics_as_writer, :class_name =&gt; "Comic", :foreign_key =&gt; :writer_id has_many :comics_as_artist, :class_name =&gt; "Comic", :foreign_key =&gt; :artist_id # some times you don't care what a person did for a comic, # you just want to know what they worked on. has_many :comics, :finder_sql =&gt; "SELECT comics.* FROM comics, people WHERE " + "`comics`.`writer_id` = `people`.`id` OR " + " `comics`.`artist_id` = `people`.`id`" end </code></pre> <p>With these relationships defined the following is possible:</p> <pre><code>@comic.artist # =&gt; Person with id matching comics.artist_id @comic.writer # =&gt; Person with id matching comics.writer_id @person.comics_as_writer # =&gt; Array of comics where @person.id matches comics.writer_id @person.comics_as_artist # =&gt; Array of comics where @person.id matches comics.artist_id @person.comics # =&gt; Array of comics where @person.id matches comics.writer_id or comics.artist_id </code></pre>
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    1. PORuby on Rails renamed foreign key
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    1. COThanks for the thorough reply. This is where I will be heading. Is that not meant to be in the Person class tho?
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    2. COGood catch. I've corrected the mistake.
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    3. COSorry for the late comment, I've just tried implementing this. It all works fine until I call <code> <% @person.comics.each do |comic| %> <%= comic.name %> <% end %> </code> This prints out the name of ther Person, not the comic. Have I missed something? When i do comic.class it corrcectly reports Comic. Sorry I've forgotten how to format things on here...
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