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THE USAGE DEPENDENCY MODEL FOR LOGICAL DATABASE DESIGN

IP.com Disclosure Number: IPCOM000128480D
Original Publication Date: 1984-Jul-01
Included in the Prior Art Database: 2005-Sep-16
Document File: 8 page(s) / 34K

Publishing Venue

Software Patent Institute

Related People

Hevia, E.: AUTHOR [+4]

Abstract

The usage dependency model is an extension to the traditional functional dependency model of relational database theory, that specifies the frequency of joint data element usage, based on process and data correspondence identified in the user requirements. The combined application of usage dependency, which is a processoriented view of data correspondence, and functional dependency, which is a nonprocessing or natural view of data correspondence, can produce a normalized database design that is efficient for current processing requirements as well as one which is adaptable to future requirements. The usage dependency model is defined and an example is developed to show its applicability to real database environments. Categories and Subject descriptions: H.2.1 [ Database Management ] : Logical Design - Normal Forms, Schema and Subschema . General Terms: Algorithms, Design, Performance, heory. Additional keywords and phrases: Relational database, functional dependencies.

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THIS DOCUMENT IS AN APPROXIMATE REPRESENTATION OF THE ORIGINAL.

THE UNIVERSITY OF MICHIGAN COMPUTING RESEARCH LABORATORY

THE USAGE DEPENDENCY MODEL FOR LOGICAL DATABASE DESIGN

E. Hevia

T.J. Teorey
CRL-TR-19-84

JULY 1984 (Revision 1)

Room 1079, East Engineering Building Ann Arbor, Michigan 48109
USA
Tel: (313) 763

The University of Michigan Computing Research Laboratory

The Usage Dependency Model for Logical Database Design [ title ]

E. Hevia
T. J. Teorey

July 1984 (Revision I)

Room 1079, East Engineering Building

Ann Arbor, Michigan 48109-1109
USA
Tel:(313)763

ABSTRACT

The usage dependency model is an extension to the traditional functional dependency model of relational database theory, that specifies the frequency of joint data element usage, based on process and data correspondence identified in the user requirements.

The combined application of usage dependency, which is a processoriented view of data correspondence, and functional dependency, which is a nonprocessing or natural view of data

University of Michigan Computing Research Laboratory Page 1 Jul 01, 1984

Page 2 of 8

THE USAGE DEPENDENCY MODEL FOR LOGICAL DATABASE DESIGN

correspondence, can produce a normalized database design that is efficient for current processing requirements as well as one which is adaptable to future requirements.

The usage dependency model is defined and an example is developed to show its applicability to real database environments.

Categories and Subject descriptions: H.2.1 [ Database Management ] : Logical Design - Normal Forms, Schema and Subschema . General Terms: Algorithms, Design, Performance, heory.

Additional keywords and phrases: Relational database, functional dependencies.

TABLE OF CONTENTS

1. Introduction.....1
2. Current methodologies.....3
3. The usage dependency model (UDM).....4
4. A design example.....8
References.....

[ Chapter ] 1 . INTRODUCTION

Logical database design involves the derivation of a database schema from a set of end-user database system requirements. Traditionally, it has been divided into two phases: conceptual design, which derives a process-independent conceptual schema that represents the real- world organization of information to be computerized, and database schema design, which derives a process-dependent database management system (DBMS) - processible schema that minimizes access cost. The schema is further refined during physical design, where cost can be absolutely defined in terms of real time or monetary value.

Techniques to assist the traditional logical database designer have been limited by their inability to evolve from a human- intensive process to a computer-automated process. Consequently, although good designs have been attained by this methodology, the individual decision steps have not been made reproducible, so that the expertise is not easily transferable from one designer to the next. In other words, two designers using current logical design methodologies today are very likely to prod...