Journal ArticleDOI
Extending the database relational model to capture more meaning
TLDR
In this paper, the relational model is extended to support atomic and molecular semantics, which is a synthesis of many ideas from the published work in semantic modeling plus the introduction of new rules for insertion, update, and deletion.Abstract:
During the last three or four years several investigators have been exploring “semantic models” for formatted databases. The intent is to capture (in a more or less formal way) more of the meaning of the data so that database design can become more systematic and the database system itself can behave more intelligently. Two major thrusts are clear. (1) the search for meaningful units that are as small as possible—atomic semantics; (2) the search for meaningful units that are larger than the usual n-ary relation—molecular semantics. In this paper we propose extensions to the relational model to support certain atomic and molecular semantics. These extensions represent a synthesis of many ideas from the published work in semantic modeling plus the introduction of new rules for insertion, update, and deletion, as well as new algebraic operators.read more
Citations
More filters
Journal ArticleDOI
Semantic database modeling: survey, applications, and research issues
Richard Hull,Roger King +1 more
TL;DR: This paper provides a tutorial introduction to the primary components of semantic models, which are the explicit representation of objects, attributes of and relationships among objects, type constructors for building complex types, ISA relationships, and derived schema components.
Journal ArticleDOI
Incomplete Information in Relational Databases
Tomasz Imielinski,Witold Lipski +1 more
TL;DR: There are precise conditions that should be satisfied in a semantically meaningful extension of the usual relational operators, such as projection, selection, union, and join, from operators on relations to operators on tables with “null values” of various kinds allowed.
Journal ArticleDOI
Logic and Databases: A Deductive Approach
TL;DR: It is shown that logic provides a convenient formalism for studying classical database problems and the representation and manipulation of deduced facts and incomplete information is shown.
Journal ArticleDOI
Database description with SDM: a semantic database model
Michael Hammer,Dennis Mc Leod +1 more
TL;DR: SDM as mentioned in this paper is a high-level semantics-based database description and structuring formalism for databases, which is designed to capture more of the meaning of an application environment than is possible with contemporary database models.
Book
Interval Neutrosophic Sets and Logic: Theory and Applications in Computing
TL;DR: This work defines the set-theoretic operators on an instance of a neutrosophic set, and calls it an Interval Neutrosophics Set (INS), and introduces a new logic system based on interval neutrosophile sets and proposed data model based on the extension of fuzzy data model and paraconsistent data model.
References
More filters
Journal ArticleDOI
A relational model of data for large shared data banks
TL;DR: In this article, a model based on n-ary relations, a normal form for data base relations, and the concept of a universal data sublanguage are introduced, and certain operations on relations are discussed and applied to the problems of redundancy and consistency in the user's model.
Book
Database Management Systems
TL;DR: New to this edition are the early coverage of the ER model, new chapters on Internet databases, data mining, and spatial databases, and a new supplement on practical SQL assignments (with solutions for instructors' use).
Journal ArticleDOI
Database abstractions: aggregation and generalization
TL;DR: A triggering mechanism for automatically maintaining these invariants during update operations is proposed, and a simple mapping of aggregation/generalization hierarchies onto owner-coupled set structures is given.
Journal ArticleDOI
System R: relational approach to database management
Morton M. Astrahan,M. W. Blasgen,Donald D. Chamberlin,Kapali P. Eswaran,Jim Gray,P. P. Griffiths,W. F. King,Raymond A. Lorie,Paul McJones,J. W. Mehl,G. R. Putzolu,Irving L. Traiger,B. W. Wade,V. Watson +13 more
TL;DR: This paper contains a description of the overall architecture and design of the system, and emphasizes that System R is a vehicle for research in database architecture, and is not planned as a product.
Book ChapterDOI
On closed world data bases
TL;DR: This paper shows that closed world evaluation of an arbitrary query may be reduced to open world evaluated of so-called atomic queries, and shows that the closed world assumption can lead to inconsistencies, but for Horn data bases no such inconsistencies can arise.