Aggregation, Persistence, and Identity in Worlds

  • Dennis G. Allard
  • David S. Wile
Conference paper
Part of the Workshops in Computing book series (WORKSHOPS COMP.)

Abstract

We have previously proposed an aggregation mechanism, called Worlds, for grouping information into conceptual units in an objectbase. This capability is neither object based nor relation based. Rather, it is concern based, consisting of an orthogonal cut through the objectbase of those aspects of objects and relations relevant to individual concerns, such as program sources, electronic mail, appointment calendars, etc. We draw an analogy with blueprints. Just as several blueprints are needed to characterize a house, several worlds are necessary to characterize a complex object. Worlds serve as units of persistence in our distributed environment where each workstation contains only a partial model of what is known about any given object. Object identity and integrity become issues in such a scheme. We opt for a weak notion of object identity based on keys or descriptions. Maintainence of contradictory information in different workstations about the same object is tolerated. Everything described is implemented, evolving, and in daily use.

Keywords

Assure Sewage Hull Stein Encapsulation 

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Copyright information

© British Computer Society 1990

Authors and Affiliations

  • Dennis G. Allard
    • 1
  • David S. Wile
    • 1
  1. 1.USC Information Sciences InstituteUSA

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