# File lib/tapkit/access/adapters/csv.rb, line 162
                def primary_keys_for_new_row( count, entity )
                        attrs = entity.primary_key_attributes
                        if attrs.size > 1 then return nil end

                        open
                        attr = attrs.first
                        column_name = attr.column_name

                        if (maxnum = @pk_cache[entity]) > 0 then
                                @pk_cache[entity] = maxnum + count
                                return _primary_keys(attr, maxnum, count)
                        end

                        maxnum = @csvdb.max_id(entity.external_name, column_name.to_i)
                        @pk_cache[entity] = maxnum + count
                        _primary_keys(attr, maxnum, count)
                end