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PODB normalization fails with first_or_create or faulty assignments
 

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    <p>This question is apparently trivial, but I am a newbie in Rails and I can't figure out where I get it wrong. I am populating associated models from an old spreadsheet. Below is a rake import task snippet. Somehow when location (Washington) is the same and already exists in the database for the Smith's post, the new assignment made for a second record <code>post.locations &lt;&lt; location</code> removes the location association with the Jones's post. My idea was to associate that same location with both people's posts. What am I missing?</p> <p><strong>import.rake</strong></p> <pre><code>data = [ { name: 'Jones', post: 'President', city: 'Washington' }, { name: 'Smith', post: 'Vice-President', city: 'Washington' }, { name: 'Peters', post: 'Janitor', city: 'New York' } ] data.each do |row| name = row[:name]; post = row[:post]; city = row[:city] person = Person.where(name: name).first_or_create post = Post.where(post: post).first_or_create location = Location.where(city: city).first_or_create post.people &lt;&lt; person post.locations &lt;&lt; location location.save; person.save; post.save end </code></pre> <p>The import above results in </p> <pre><code>person1 = Person.find_by_name("Jones"); person1.posts.first.locations.first == nil person2 = Person.find_by_name("Smith"); person2.posts.first.locations.first.city == "Washington" person3 = Person.find_by_name("Peters"); person3.posts.first.locations.first.city == "New York" </code></pre> <p><strong>location.rb</strong></p> <pre><code>class Location &lt; ActiveRecord::Base belongs_to :post attr_accessible :city end </code></pre> <p><strong>person.rb</strong></p> <pre><code>class Person &lt; ActiveRecord::Base attr_accessible :name has_many :occupations has_many :posts, through: :occupations end </code></pre> <p><strong>post.rb</strong></p> <pre><code>class Post &lt; ActiveRecord::Base attr_accessible :post has_many :occupations has_many :people, through: :occupations has_many :locations end </code></pre> <p><strong>occupation.rb</strong></p> <pre><code>class Occupation &lt; ActiveRecord::Base belongs_to :person belongs_to :post attr_accessible :person_id, :post_id, :since, :till end </code></pre>
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    1. USAlexei Danchenkov
    1. USAlexei Danchenkov
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      1. VTUpMod
    1. COUse `save!` (with the bang), which will return an error instead of silently failing. Then you'll be able to see why/if something isn't saving.
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      1. USbricker
    2. COAlso might help to see your Occupation class.
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      1. USbricker
    3. COThanks for the hint and I keep checking. The data actually gets saved. The consequent save REMOVES the association from the first post when assigning the same location to the second post.
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      1. USAlexei Danchenkov
 

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