Method: ActiveRecord::CounterCache::ClassMethods#reset_counters

Defined in:
activerecord/lib/active_record/counter_cache.rb

#reset_counters(id, *counters, touch: nil) ⇒ Object

Resets one or more counter caches to their correct value using an SQL count query. This is useful when adding new counter caches, or if the counter has been corrupted or modified directly by SQL.

Parameters

  • id - The id of the object you wish to reset a counter on.

  • counters - One or more association counters to reset. Association name or counter name can be given.

  • :touch - Touch timestamp columns when updating. Pass true to touch updated_at and/or updated_on. Pass a symbol to touch that column or an array of symbols to touch just those ones.

Examples

# For the Post with id #1, reset the comments_count
Post.reset_counters(1, :comments)

# Like above, but also touch the updated_at and/or updated_on
# attributes.
Post.reset_counters(1, :comments, touch: true)


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# File 'activerecord/lib/active_record/counter_cache.rb', line 34

def reset_counters(id, *counters, touch: nil)
  object = find(id)

  updates = {}
  counters.each do |counter_association|
    has_many_association = _reflect_on_association(counter_association)
    unless has_many_association
      has_many = reflect_on_all_associations(:has_many)
      has_many_association = has_many.find { |association| association.counter_cache_column && association.counter_cache_column.to_sym == counter_association.to_sym }
      counter_association = has_many_association.plural_name if has_many_association
    end
    raise ArgumentError, "'#{name}' has no association called '#{counter_association}'" unless has_many_association

    if has_many_association.is_a? ActiveRecord::Reflection::ThroughReflection
      has_many_association = has_many_association.through_reflection
    end

    foreign_key  = has_many_association.foreign_key.to_s
    child_class  = has_many_association.klass
    reflection   = child_class._reflections.values.find { |e| e.belongs_to? && e.foreign_key.to_s == foreign_key && e.options[:counter_cache].present? }
    counter_name = reflection.counter_cache_column

    count_was = object.send(counter_name)
    count = object.send(counter_association).count(:all)
    updates[counter_name] = count if count != count_was
  end

  if touch
    names = touch if touch != true
    names = Array.wrap(names)
    options = names.extract_options!
    touch_updates = touch_attributes_with_time(*names, **options)
    updates.merge!(touch_updates)
  end

  unscoped.where(primary_key => [object.id]).update_all(updates) if updates.any?

  true
end