destroy

# File activerecord/lib/active_record/locking/optimistic.rb, line 109
        def destroy #:nodoc:
          return super unless locking_enabled?

          unless new_record?
            lock_col = self.class.locking_column
            previous_value = send(lock_col).to_i

            table = self.class.arel_table
            predicate = table[self.class.primary_key].eq(id)
            predicate = predicate.and(table[self.class.locking_column].eq(previous_value))

            affected_rows = self.class.unscoped.where(predicate).delete_all

            unless affected_rows == 1
              raise ActiveRecord::StaleObjectError, "Attempted to delete a stale object: #{self.class.name}"
            end
          end

          @destroyed = true
          freeze
        end