Ruby on Rails latest stable (v4.1.8) - 0 notes - Class: ClassMethods
increment_counter(counter_name, id) public

Increment a numeric field by one, via a direct SQL update.

This method is used primarily for maintaining counter_cache columns that are used to store aggregate values. For example, a DiscussionBoard may cache posts_count and comments_count to avoid running an SQL query to calculate the number of posts and comments there are, each time it is displayed.


  • counter_name - The name of the field that should be incremented.

  • id - The id of the object that should be incremented or an Array of ids.


# Increment the post_count column for the record with an id of 5
DiscussionBoard.increment_counter(:post_count, 5)
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