scope_counter is a simple implementation of counter_cache functionality for models scopes with ActiveRecord
Install
gem 'scope_counter'and run bundle install from your shell.
Usage
Create columns in db according to scopes in your model ("#{scope_name}_#{table_name}_count"):
t.integer :usefull_utilities_count, :default => 0
t.integer :useless_utilities_count, :default => 0
t.integer :utilities_count, :default => 0List in array scopes, which you want to create counter cache for, as :conter_cache option (if you want to add a default behavior just add :all in array):
class Advice < ActiveRecord::Base
has_many :utilities
end
class Utility < ActiveRecord::Base
belongs_to :advice, :counter_cache => [:all,:usefull, :useless]
scope :usefull, where(:usefull => true)
scope :useless, where(:usefull => false)
end
advice = Advice.create
advice.usefull_utilities_count # => 0
advice.utilities.usefull.create
advice.usefull_utilities_count # => 1
advice.utilities_count # => 1