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Precedency control and other semantic integrity issues in a workbench databaseMost database systems model the current state of a system of real world discrete and simple entities together with their relationships. By examining instead a database system that is a workbench and models more complicated entities, a fresh perspective is gained. Specifically, semantic integrity is analysed. Four aspects distinct from physical integrity are identified, namely - access, failure, concurrency and precedency. Access control is shown to be the consequence of semantic interdependency between data and its matching semantic routines. Failure, concurrency precedency controls are concerned with preventing processes interfering with each other. Precedency is a new concept in the database context. It expresses a constraint between processes that act on the database. As processes create, update and delete entities they in general obey a partial ordering imposed by the semantics of their actions. Precedency control ensures that data remains consistent with respect to this partial order.
Document ID
19850014909
Acquisition Source
Legacy CDMS
Document Type
Other
Authors
Dampney, C. N. G.
(MacQuarie Univ. North Ryde, Australia)
Date Acquired
August 12, 2013
Publication Date
January 1, 1983
Publication Information
Publication: MAGSAT Anomaly Field Data of the Crustal Properties of Australia
Subject Category
Earth Resources And Remote Sensing
Accession Number
85N23220
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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