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Module: Mongoid::Association::Referenced::CounterCache::ClassMethods

Relationships & Source Files
Extension / Inclusion / Inheritance Descendants
Extended In:
::Mongoid::Association, ::Mongoid::Composable, ::Mongoid::Document
Defined in: lib/mongoid/association/referenced/counter_cache.rb

Instance Method Summary

Instance Method Details

#decrement_counter(counter_name, id)

Decrement the counter name from the entries that match the id by one. This method is used on associations callbacks when counter_cache is enabled

Examples:

Decrement comments counter

Post.decrement_counter(:comments_count, '50e0edd97c71c17ea9000001')

Parameters:

  • counter_name (Symbol) —

    Counter cache name

  • id (String) —

    The id of the object that will have its counter decremented.

[ GitHub ] 

  


# File 'lib/mongoid/association/referenced/counter_cache.rb', line 84



def decrement_counter(counter_name, id)
  update_counters(id, counter_name.to_sym => -1)
end


  








  

    #increment_counter(counter_name, id)  
  



  

    

Increment the counter name from the entries that match the id by one. This method is used on associations callbacks when counter_cache is enabled


  





    

    
Examples:

        


Increment comments counter



      
Post.increment_counter(:comments_count, '50e0edd97c71c17ea9000001')

  


Parameters:


    
  
  • 
    counter_name
    (Symbol)
—    
    

    Counter cache name
    

    
  
    • 
  
  • 
    id
    (String)
—    
    

    The id of the object that will have its counter incremented.
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/mongoid/association/referenced/counter_cache.rb', line 71



def increment_counter(counter_name, id)
  update_counters(id, counter_name.to_sym => 1)
end


  








  

    #reset_counters(id, *counters)  
  



  

    

Reset the given counter using the .count() query from the db. This method is useful in case that a counter got corrupted, or a new counter was added to the collection.


  





    

    
Examples:

        


Reset the given counter cache



      
Post.reset_counters('50e0edd97c71c17ea9000001', :comments)

  


Parameters:





  [ GitHub ]


  

  


# File 'lib/mongoid/association/referenced/counter_cache.rb', line 39



def reset_counters(id, *counters)
  document = id.is_a?(Document) ? id : find(id)
  counters.each do |name|
    relation_association = relations[name]
    counter_name = relation_association.inverse_association.counter_cache_column_name
    document.update_attribute(counter_name, document.send(name).count)
  end
end


  








  

    #update_counters(id, counters)  
  



  

    

Update the given counters by the value factor. It uses the atomic $inc command.


  





    

    
Examples:

        


Add 5 to comments counter and remove 2 from likes



      
counter.
Post.update_counters('50e0edd97c71c17ea9000001',
           :comments_count => 5, :likes_count => -2)

  


Parameters:


    
  
  • 
    id
    (String)
—    
    

    The id of the object to update.
    

    
  
    • 
  
  • 
    counters
    (Hash)
  
    • 





  [ GitHub ]


  

  


# File 'lib/mongoid/association/referenced/counter_cache.rb', line 58



def update_counters(id, counters)
  where(:_id => id).inc(counters)
end