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PORuby on Rails: create a relationship that combines three other relationships
 

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  1. PORuby on Rails: create a relationship that combines three other relationships
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    <p>I'm attempting to create a relationship that combines three other relationships. The initial three are all of the same class, I'd like like a conglomerate, however I can't find a nice "arel" way of doing it.</p> <p>Here is an example of what I'm trying to do.</p> <p>The SQL query that works is</p> <pre><code>SELECT `records`.* FROM `records` INNER JOIN `memberships` ON `records`.`subject_membership_id` = `memberships`.`id` OR `records`.`recorder_membership_id` = `memberships`.`id` OR `records`.`subject_membership_id` = `memberships`.`id` WHERE `memberships`.`group_id` = 4 </code></pre> <p>Of course, I want to do that the rails way. Here is what I have so far. It should be pretty self-explanitory, so I won't waste your time explaining it further.</p> <pre><code>class Group &lt; ActiveRecord::Base has_many :recorded_records, :through =&gt; :memberships, :source =&gt; :recorded_records, :class_name =&gt; "Record" has_many :reported_records, :through =&gt; :memberships, :source =&gt; :reported_records, :class_name =&gt; "Record" has_many :reviewed_records, :through =&gt; :memberships, :source =&gt; :reviewed_records, :class_name =&gt; "Record" #has_many :records through recorded_records, reported_records, reviewed_records?? # Psuedo code above... Wondering how best to do this. I've tried... def records recorded_records | reported_records | reviewed_records end # But that makes three seperate database queries when what I really want is... # SELECT `records`.* FROM `records` INNER JOIN `memberships` ON `records`.`subject_membership_id` = `memberships`.`id` OR `records`.`recorder_membership_id` = `memberships`.`id` OR `records`.`subject_membership_id` = `memberships`.`id` WHERE `memberships`.`group_id` = 4 end </code></pre> <p>You guys rock! Thanks :)</p>
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    1. UStereško
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    1. COcan you show the `Membership` model content?
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      1. PORuby on Rails: create a relationship that combines three other relationships
      1. USManoj Monga
 

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