Value Assignment of Complex Objects-Aggregation Operations

This paper introduces the common features of aggregations of objects.A general procedure of aggregation operations is outlined based on Smallworld.Depending on the characteristics of attributes,aggregations of attribute values can be boiled down to three basic groups.And an administrative area is taken for the experiment in aggregation operations.For the realization of data aggregations,magik-an object-oriented language supported by Smallworld is adopted to implement of those operations.