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POGet object of relation n:m in Ruby on Rails
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2012-12-07T17:20:25.537
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I have two models: <ol> <li>Perfiles</li> <li>Modulos</li> </ol> And the relationship between them is: Many to Many, there is a table to map relation: modulos_perfiles I need get all "modulos" that belongs to "perfil".. I have this: <pre><code><% @perfiles.each do |perfil| %> <% @m = perfil.modulo.last %> <%= @m.ruta %> <% end %> </code></pre> but I get this error: <blockquote> undefined method "ruta" for nil:NilClass </blockquote> Where "ruta" is a column of "modulo" table. I made this: <pre><code><% @perfiles.each do |perfil| %> <% @m = perfil.modulo.last %> <%= debug @m %> <% end %> </code></pre> And I can see all attributes of @m object so: ruby/object:Modulo attributes: <ul> <li>id: 7 </li> <li>descripcion: Busquedas</li> <li>ruta: /busquedas</li> <li>created_at: 2012-11-25 02:23:51.984916000 Z</li> <li>updated_at: 2012-11-25 02:23:51.984916000 Z </li> </ul> But I don't understand why I cannot get this attributes with: <pre><code><%= @m.ruta %> </code></pre> Any idea?, thanks! UPDATE My model classes are: <pre><code>class Perfil < ActiveRecord::Base has_many :usuario has_and_belongs_to_many :modulo end class Modulo < ActiveRecord::Base has_and_belongs_to_many :perfiles end class ModulosPerfiles < ActiveRecord::Base end </code></pre> ** <h2>ANSWER</h2> ** I don't have enough reputation to publish answer. I've resolved: I made this: <pre><code><% @perfiles.each do |perfil| %> <% perfil.modulo.each do |modulo| %> <%= modulo.ruta %> <% end %> <% end %> </code></pre> And so I can get any attribute of object "modulo". Thanks.
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<ruby-on-rails><ruby><ruby-on-rails-3>
Title
Get object of relation n:m in Ruby on Rails
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