relation_for_destroy

# File activerecord/lib/active_record/locking/optimistic.rb, line 117
        def relation_for_destroy
          relation = super

          if locking_enabled?
            locking_column = self.class.locking_column
            relation = relation.where(locking_column => read_attribute_before_type_cast(locking_column))
          end

          relation
        end