ruby on rails - Get changed attributes on after_update callback -

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i'm trying make conditional after_update, have following:

  after_update |participant|     rails.logger.info "#{self.previous_changes} changed."     if self.previous_changes.include?(:current_distance)       #do stuff ...     end   end

the logger prints empty hash: {}

how can check attribute has been changed?

i using: participant.update_attribute(:current_distance, distance) update attribute.

you want use changes not previous_changes. still in same save transaction looking in changes. previous_changes won't have information until after update completes.


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