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PORails ActiveRecord: legacy table without primary key shows nil for result?
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  1. PORails ActiveRecord: legacy table without primary key shows nil for result?
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    copied!<p>I've got a Rails app that'll be sitting on top of a legacy database with some ugly tables that I'm having to deal with. One is a <code>feature_attributes</code> table related to <code>features</code>. Problem is that this <code>feature_attributes</code> table doesn't have a primary key. I wouldn't think that'd be a problem, but evidently it is. I've got my model name which is different from the table name, but I'm using <code>set_table_name</code> to specify the right one.</p> <pre><code>class Feature &lt; ActiveRecord::Base has_many :feature_attributes end class FeatureAttribute &lt; ActiveRecord::Base set_table_name 'feature_attribute' belongs_to :feature end </code></pre> <p>Once I load a feature that I know has related <code>feature_attributes</code> and call <code>feature.feature_attributes</code> on it, I get <code>nil</code>. Matter of fact, even <code>FeatureAttribute.first</code> gives me <code>nil</code>. The result of <code>FeatureAttribute.any?</code> returns <code>false</code>. I'm worried that ActiveRecord isn't reading any of the data from the table because there isn't a primary key. Is that what's going on here?</p> <p>The <code>feature_attribute</code> table has the following columns.</p> <pre><code>feature_id attribute_name attribute_value created_date modified_date </code></pre> <p>Help!</p> <p><em>I'll also note that running the generated SQL directly against the MySQL server actually gets me the rows I want.</em></p> <pre><code>SELECT `feature_attribute`.* FROM `feature_attribute` WHERE `feature_attribute`.`feature_id` = 24; </code></pre> <p><strong>EDIT</strong>: I am so sorry. Next time I'll learn to check my <code>database.yml</code>. Evidently I was reading from a test database that had an identical feature table, but the <code>feature_attribute</code> table was totally empty.</p> <p>I feel like a moron. Thanks for your help, everyone; I'm up voting you all for your troubles. I did like just about everybody's answer. (Can I down vote myself? :))</p>
 

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