# File lib/symetrie_com/acts_as_better_nested_set.rb, line 307
          def check_all
            total = 0
            transaction do
              # if there are virtual roots, only call check_full_tree on the first, because it will check other virtual roots in that tree.
              total = roots.inject(0) {|sum, r| sum + (r[r.left_col_name] == 1 ? r.check_full_tree : 0 )}
              raise ActiveRecord::ActiveRecordError, "Scope problems or nodes without a valid root" unless acts_as_nested_set_options[:class].count == total
            end
            return total
          end