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copied!<p>I recently came across this same problem (Rails 3.2.3). Looks like it has yet to be fixed, so I had to go ahead and make a fix. Below is how I amended ActiveRecord::Base and utilize after_update callback to keep my counter_caches in sync.</p> <p><strong>Extend ActiveRecord::Base</strong></p> <p>Create a new file <code>lib/fix_counters_update.rb</code> with the following:</p> <pre><code>module FixUpdateCounters def fix_updated_counters self.changes.each {|key, value| # key should match /master_files_id/ or /bibls_id/ # value should be an array ['old value', 'new value'] if key =~ /_id/ changed_class = key.sub(/_id/, '') changed_class.camelcase.constantize.decrement_counter(:"#{self.class.name.underscore.pluralize}_count", value[0]) unless value[0] == nil changed_class.camelcase.constantize.increment_counter(:"#{self.class.name.underscore.pluralize}_count", value[1]) unless value[1] == nil end } end end ActiveRecord::Base.send(:include, FixUpdateCounters) </code></pre> <p>The above code uses the <a href="http://api.rubyonrails.org/classes/ActiveModel/Dirty.html">ActiveModel::Dirty</a> method <code>changes</code> which returns a hash containing the attribute changed and an array of both the old value and new value. By testing the attribute to see if it is a relationship (i.e. ends with /_id/), you can conditionally determine whether <code>decrement_counter</code> and/or <code>increment_counter</code> need be run. It is essnetial to test for the presence of <code>nil</code> in the array, otherwise errors will result.</p> <p><strong>Add to Initializers</strong></p> <p>Create a new file <code>config/initializers/active_record_extensions.rb</code> with the following:</p> <p><code>require 'fix_update_counters'</code></p> <p><strong>Add to models</strong></p> <p>For each model you want the counter caches updated add the callback:</p> <pre><code>class Comment < ActiveRecord::Base after_update :fix_updated_counters .... end </code></pre>

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