Views in H-PCTE

Kelter, Udo

H-PCTE is a transparently distributed, structurally object-oriented database system. H-PCTE is designed for large distributed systems and addresses related problems: it allows isolated sites to operate autonomously on locally reachable data and even to extend or modify locally reachable metadata. The distribution model has had a very strong impact on the data model and the design of H-PCTE. H-PCTE's metabase, which contains the type definitions, is distributed and partly replicated. There is no centralized conceptual schema of the object base: each process reads or updates the object base only via a view, which is derived from locally reachable parts of the metabase. Views support data-independence of applications and restrict access to data on the basis of their type, i.e. they perform "type-level accesscontrols". The main features of the view concept are: it supports multiple inheritance, arbitrary security policies for inheritance can be realized, nested working groups are supported, access can be explicitly denied, and the administration of type definitions and access rights is completely decentralized through the concept of owners of types in the metabase.

Vorschau

Zitieren

Zitierform:

Kelter, Udo: Views in H-PCTE. Hagen 1991. FernUniversität in Hagen.

Zugriffsstatistik

Gesamt

Volltextzugriffe:
Metadatenansicht:

12 Monate

Volltextzugriffe:
Metadatenansicht:

Rechte

Nutzung und Vervielfältigung:
Alle Rechte vorbehalten

Export

powered by MyCoRe