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POActiveRecord find_or_build_by
primarykey
Id
6833663
data
AcceptedAnswerId
6894504
AnswerCount
3
ClosedDate
CommentCount
5
CommunityOwnedDate
CreationDate
2011-07-26T16:52:22.760
FavoriteCount
4
LastActivityDate
2015-06-02T14:45:10.243
LastEditDate
2017-05-23T10:27:59.787
LastEditorUserId
-1
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426247
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0
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1
Score
9
ViewCount
6507
LastEditorDisplayName
text
Body
<p>I would like to perform:</p> <pre><code> XXX.find_or_build_by_language_id(attributes) </code></pre> <p>I found</p> <pre><code> XXX.find_or_initialize_by_language_id(attributes) </code></pre> <p>but that only set language_id and no other attributes. Even if I manually sets the attributes, the record is not saved when I perform XXX.save.</p> <p>I just read <a href="https://stackoverflow.com/questions/4844458">Rails - find or create - is there a find or build?</a>, which seems related to my problem but does not fit my needs.</p> <h2>Edit</h2> <p>Let's use this scenario</p> <pre><code># db/migrations/create_models.rb class CreateModels < ActiveRecord::Migration def self.up create_table :companies do |t| t.string :name end create_table :employees do |t| t.string :name t.string :city t.references :company end end end </code></pre> <p>-</p> <pre><code># app/models/employee.rb class Employee < ActiveRecord::Base belongs_to :company end </code></pre> <p>-</p> <pre><code># app/models/company.rb class Company < ActiveRecord::Base has_many :employees end </code></pre> <p>-</p> <pre><code># rails console :001> c = Company.new => #<Company id: nil, name: nil> :002> c.employees => [] :003> e = c.employees.find_or_initialize_by_name(:name => 'foo', :city => 'bar') => #<Employee id: nil, name: "foo", city: "bar", company_id: nil> :004> c.employees => [] :005> c.save => true :006> c.employees => [] :007> e.save => true :008> c = Company.first => #<Company id: 1, name: nil> :009> c.employees => [#<Employee id: 1, name: "foo", city: "bar", company_id: 1>] :010> e = c.employees.find_or_initialize_by_name(:name => 'foo', :city => 'baz') => #<Employee id: 1, name: "foo", city: "bar", company_id: 1> :011> e.city = 'baz' => "baz" :012> c.employees => [#<Employee id: 1, name: "foo", city: "bar", company_id: 1>] :013 > c.save => true :014> c.employees => [#<Employee id: 1, name: "foo", city: "bar", company_id: 1>] </code></pre> <h2>Problems</h2> <ol> <li>:004 => The Employee from :003 is not added to c.employees</li> <li>:006 => The Employee from :003 is saved with c</li> <li>:010 => The city attribute of employee is not set</li> <li>:014 => THe city attribute of employee is not updated when saving company</li> </ol>
Tags
<ruby-on-rails><ruby><ruby-on-rails-3><activerecord>
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