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PORails Joins and include columns from joins table
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  1. PORails Joins and include columns from joins table
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    copied!<p>I don't understand how to get the columns I want from rails. I have two models - A User and a Profile. A User :has_many Profile (because users can revert back to an earlier version of their profile):</p> <pre><code>&gt; DESCRIBE users; +----------------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +----------------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | username | varchar(255) | NO | UNI | NULL | | | password | varchar(255) | NO | | NULL | | | last_login | datetime | YES | | NULL | | +----------------+--------------+------+-----+---------+----------------+ </code></pre> <p>&nbsp;</p> <pre><code>&gt; DESCRIBE profiles; +----------------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +----------------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | user_id | int(11) | NO | MUL | NULL | | | first_name | varchar(255) | NO | | NULL | | | last_name | varchar(255) | NO | | NULL | | | . . . . . . | | . . . . . . | | . . . . . . | +----------------+--------------+------+-----+---------+----------------+ </code></pre> <p>In SQL, I can run the query:</p> <pre><code>&gt; SELECT * FROM profiles JOIN users ON profiles.user_id = users.id LIMIT 1; +----+-----------+----------+---------------------+---------+---------------+-----+ | id | username | password | last_login | user_id | first_name | ... | +----+-----------+----------+---------------------+---------+---------------+-----+ | 1 | john | ****** | 2010-12-30 18:04:28 | 1 | John | ... | +----+-----------+----------+---------------------+---------+---------------+-----+ </code></pre> <p>See how I get all the columns for BOTH tables JOINED together? However, when I run this same query in Rails, I don't get all the columns I want - I only get those from Profile:</p> <pre><code># in rails console &gt;&gt; p = Profile.joins(:user).limit(1) &gt;&gt; [#&lt;Profile ...&gt;] &gt;&gt; p.first_name &gt;&gt; NoMethodError: undefined method `first_name' for #&lt;ActiveRecord::Relation:0x102b521d0&gt; from /Library/Ruby/Gems/1.8/gems/activerecord-3.0.1/lib/active_record/relation.rb:373:in `method_missing' from (irb):8 # I do NOT want to do this (AKA I do NOT want to use "includes") &gt;&gt; p.user &gt;&gt; NoMethodError: undefined method `user' for #&lt;ActiveRecord::Relation:0x102b521d0&gt; from /Library/Ruby/Gems/1.8/gems/activerecord-3.0.1/lib/active_record/relation.rb:373:in method_missing' from (irb):9 </code></pre> <p>I want to (efficiently) return an object that has all the properties of Profile and User together. I don't want to :include the user because it doesn't make sense. The user should always be part of the most recent profile as if they were fields within the Profile model. How do I accomplish this? </p> <p>I think the problem has something to do with the fact that the Profile model doesn't have attributes for User...</p>
 

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