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POTrying to obtain author of answer in nested model gives `Called id for nil, which would mistakenly be 4`
 

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  1. POTrying to obtain author of answer in nested model gives `Called id for nil, which would mistakenly be 4`
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    <p>today my error is <code>Called id for nil, which would mistakenly be 4 -- if you really wanted the id of nil, use object_id</code>.</p> <p>I've got models &amp; controllers for: User, Ticket, Answers defined in such way:</p> <p><code>User</code> has many <code>Answers</code> &amp; <code>Tickets</code></p> <p><code>Ticket</code> has many <code>Answers</code> </p> <p><code>Answer</code> belongs to <code>User</code> &amp; belongs to <code>Ticket</code></p> <p>The error appears when in <code>Ticket</code> view I'm trying to display <code>Answers</code> author (<code>User</code>) doing it like this:</p> <p><code>Ticket Load (0.2ms) SELECT "tickets".* FROM "tickets" LIMIT 1 =&gt; #&lt;Ticket id: 8, topic: "This is sample question", message: "This is Sample question with &lt;h1&gt;Some&lt;/h1&gt; HTML! &lt;p...", user_id: 1, category_id: 2, created_at: "2013-01-15 12:24:20", updated_at: "2013-01-15 12:24:20", answers_count: 1&gt;</code></p> <p><code>Answer Load (0.2ms) SELECT "answers".* FROM "answers" LIMIT 1 =&gt; #&lt;Answer id: 6, ticket_id: 8, user_id: 1, message: "This is answer to the sample question with use of h...", created_at: "2013-01-15 12:26:46", updated_at: "2013-01-15 12:26:46"&gt;</code></p> <p><code>User Load (0.2ms) SELECT "users".* FROM "users" LIMIT 1 =&gt; #&lt;User id: 1, username: "mickula", email: "xx@xx.com", password_hash: "$2a$10$Hty2ekM3t8Dqf0CvZm5zEOwVnXAoytimW9tIOxtfjwNG...", password_salt: "$2a$10$Hty2ekM3t8Dqf0CvZm5zEO", created_at: "2013-01-12 16:55:00", updated_at: "2013-01-12 16:55:00", permission_level: nil&gt;</code></p> <pre><code>User.first.answers User Load (0.2ms) SELECT "users".* FROM "users" LIMIT 1 Answer Load (0.1ms) SELECT "answers".* FROM "answers" WHERE "answers"."user_id" = 1 =&gt; [#&lt;Answer id: 6, ticket_id: 8, user_id: 1, message: "This is answer to the sample question with use of h...", created_at: "2013-01-15 12:26:46", updated_at: "2013-01-15 12:26:46"&gt;] </code></pre> <p>When I try to display answer <code>a.user.username</code> it returns error:</p> <p><code>undefined method username for nil:NilClass</code></p> <p>So it seems like that answer is not connected with user. Could you point me where I did mistake and why it behaves like that? I would like to mention that I did it this way for Tickets and there I can display author of ticket with <code>@ticket.user.username</code> </p> <p>Models:</p> <pre><code>class Ticket &lt; ActiveRecord::Base attr_accessible :topic, :message, :user, :category, :category_id has_many :answers belongs_to :user belongs_to :category end class Answer &lt; ActiveRecord::Base attr_accessible :ticket, :user, :message belongs_to :user belongs_to :ticket, :counter_cache =&gt; true end class User &lt; ActiveRecord::Base attr_accessible :username, :email, :password, :password_confirmation has_many :tickets has_many :answers end </code></pre> <p>Controller's partials:</p> <pre><code>class TicketsController &lt; ApplicationController before_filter :login_required before_filter :admin_required, :only =&gt; [:index, :show] def index @tickets = Ticket.all end def show @ticket = Ticket.find(params[:id]) end end class AnswersController &lt; ApplicationController def create t_attr = params[:answer].merge :user =&gt; current_user @ticket = Ticket.find(params[:ticket_id]) @answer = @ticket.answers.create(t_attr) redirect_to ticket_path(@ticket) end end </code></pre> <p>Edit: Through console I can obtain answer's author userdata:</p> <pre><code>Ticket.first.answers.first.user Ticket Load (0.2ms) SELECT "tickets".* FROM "tickets" LIMIT 1 Answer Load (0.1ms) SELECT "answers".* FROM "answers" WHERE "answers"."ticket_id" = 8 LIMIT 1 User Load (0.1ms) SELECT "users".* FROM "users" WHERE "users"."id" = 1 LIMIT 1 =&gt; #&lt;User id: 1, username: "mickula", email: "xx@xx.com", password_hash: "$2a$10$Hty2ekM3t8Dqf0CvZm5zEOwVnXAoytimW9tIOxtfjwNG...", password_salt: "$2a$10$Hty2ekM3t8Dqf0CvZm5zEO", created_at: "2013-01-12 16:55:00", updated_at: "2013-01-12 16:55:00", permission_level: nil&gt; </code></pre> <p>Ticket view:</p> <pre><code>&lt;span class="pull-right"&gt;by &lt;strong&gt;&lt;%=h @ticket.user.username %&gt;&lt;/strong&gt; on &lt;i&gt;&lt;%=h @ticket.created_at %&gt; in &lt;strong&gt;&lt;%= @ticket.category.name %&gt;&lt;/strong&gt;&lt;/i&gt;&lt;/span&gt; &lt;p&gt; &lt;strong&gt;Message:&lt;/strong&gt;&lt;br&gt; &lt;%=h @ticket.message %&gt; &lt;/p&gt; &lt;h3&gt;Replies&lt;/h3&gt; &lt;%= form_for([@ticket, @ticket.answers.build]) do |f| %&gt; &lt;%= f.label :message %&gt; &lt;br&gt; &lt;%= f.text_area :message, :cols =&gt; "50", :rows =&gt; "6", :class=&gt; "span12" %&gt;&lt;br&gt; &lt;%= f.submit %&gt; &lt;% end %&gt; &lt;% @ticket.answers.each do |a| %&gt; &lt;%= h a.message %&gt; &lt;%= a.user.username %&gt; &lt;%= a.created_at %&gt; &lt;% end %&gt; &lt;/div&gt; </code></pre> <p>Workaround:</p> <pre><code> &lt;% @ticket.answers.each do |a| %&gt; &lt;%= h a.message %&gt; &lt;%= a.user.username if a.user %&gt; &lt;%= a.created_at %&gt; &lt;% end %&gt; </code></pre> <p>With this condition everything works. Seems like Loop is doing 1 extra iteration, even if there's no answers.</p>
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    1. PO
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      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USmic-kul
    1. USmic-kul
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
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      1. PTAnswer
    1. This table or related slice is empty.
    1. COAre you sure there is a user with `id = 1`? If not, that would explain why you get nils everywhere.
      singulars
      1. POTrying to obtain author of answer in nested model gives `Called id for nil, which would mistakenly be 4`
      1. USChris Salzberg
    2. CO100% sure. Updated the question with result of query from users. I believe if user wouldn't exist I couldn't display it for Ticket
      singulars
      1. POTrying to obtain author of answer in nested model gives `Called id for nil, which would mistakenly be 4`
      1. USmic-kul
    3. COIn that case, there must be something else happening in your view or controller. Can you post the `Ticket` view code, and any partials (if there are any)? That might help.
      singulars
      1. POTrying to obtain author of answer in nested model gives `Called id for nil, which would mistakenly be 4`
      1. USChris Salzberg
 

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