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POHow to get info from a third table when joining two tables?
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9980387
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2012-04-02T16:45:43.807
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2012-04-04T20:26:58.930
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2012-04-03T09:56:45.997
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I have this schema: <img src="https://i.stack.imgur.com/oKe9r.png" alt="enter image description here"> <ul> <li>There is a table for persons.</li> <li>Each person has one "info" table.</li> <li>Persons can have friends. This is stored in another table called "friends", which has a foreign key for the person, and another one for his friend (both are pointing to the "person" table).</li> </ul> "person" model: <pre><code>class Person < ActiveRecord::Base has_one :info has_many :friends end </code></pre> "info" model: <pre><code>class Info < ActiveRecord::Base belongs_to :person attr_accessible :description end </code></pre> "friends" model: <pre><code>class Friend < ActiveRecord::Base belongs_to :person attr_accessible :friend_id end </code></pre> Let's suppose we have 2 persons: person1 and person2. Each one with a record in the "info" table storing its description. And let's suppose that person2 is a friend of person1. content of "person" table: <blockquote> id: 1 id: 2 </blockquote> content of "info" table: <blockquote> id: 1, person_id: 1, description: "This is person 1, our main dude." id: 2, person_id: 2, description: "This is person 2, our secondary dude." </blockquote> content of "friends" table: <blockquote> id: 1, person_id: 1, friend_id: 2 </blockquote> If I want to get person1's friends I do this: <pre><code>Person.first.friends </code></pre> This will give me: <blockquote> id: 1, person_id: 1, friend_id: 2 </blockquote> Now, how do I add the "info" content for each row?
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<ruby-on-rails><ruby-on-rails-3><activerecord>
Title
How to get info from a third table when joining two tables?
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1. USDavid Morales
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1. USDavid Morales
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