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POWeird results when testing model associations in Rails Console
 

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  1. POWeird results when testing model associations in Rails Console
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    <p>I have a User model, an Event Model, an Event Priority Model and a Event Type Model. Model code as follows:</p> <pre><code>class Event &lt; ActiveRecord::Base belongs_to :user belongs_to :event_priority belongs_to :event_type attr_accessible :name, :raised_date, :location, :description, :longtitude, :latitude attr_protected :raised_user_id, :event_priority_id, :event_type_id end class EventPriority &lt; ActiveRecord::Base has_many :events has_many :users, :through =&gt; :events has_many :event_types, :through =&gt; :events end class EventType &lt; ActiveRecord::Base has_many :events has_many :users, :through =&gt; :events has_many :event_priorities, :through =&gt; :events end class User &lt; ActiveRecord::Base attr_accessor :password attr_accessible :first_name, :last_name, :full_name, :password, password_confirmation has_many :events, :foreign_key =&gt; "raised_user_id", :dependent =&gt; :destroy has_many :event_priorities, :through =&gt; :events has_many :event_types, :through =&gt; :events end </code></pre> <p>Can anyone explain the inability to get from the Event back to the User in the following rails console example?</p> <pre><code>irb(main):027:0&gt; @user = User.find(2) =&gt; Returns the user with an ID of 2. irb(main):028:0&gt; @user.events =&gt; Returns all events for that user. irb(main):029:0&gt; @user.events.first.user =&gt; nil --HUH???? irb(main):031:0&gt; @event = @user.events.first =&gt; Saves and returns the first event created by the user. irb(main):032:0&gt; @event.user =&gt; nil --Again, WHY?? irb(main):033:0&gt; @events = Event.all =&gt; Saves and returns all events. irb(main):035:0&gt; @events.first.user NoMethodError: You have a nil object when you didn't expect it! You might have expected an instance of Array. The error occurred while evaluating nil.first from (irb):35 from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/activemodel-3.0. 6/lib/active_model/attribute_methods.rb:279 -- AGAIN, WHY? </code></pre>
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    1. USraoul_dev
    1. USraoul_dev
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    1. COCan you post your model assocations for `:user` and `:event`?
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      1. USAdam Eberlin
    2. COOk I get it! So a :custom_key has to be specified on BOTH sides of a Rails model association, in my case has_many and belongs_to.
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      1. USraoul_dev
 

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