Encyclopedia of Database Systems

2018 Edition
| Editors: Ling Liu, M. Tamer Özsu

Diagram

  • Carlo Batini
Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-8265-9_814

Synonyms

Diagram; Diagrammatic Representation; Graph; Graphic

Definition

A diagram is (i) a set of symbols selected in an alphabet of elementary shapes, such as rectangles, circles, and complex shapes, built by composing elementary shapes, and (ii) a set of connections linking symbols, such as straight lines, curved lines, directed lines, etc. Diagrams are used to visualize in all aspects of data base design and usage a wide set of concepts, artifacts, schemas, values, such as conceptual schemas, logical schemas, UML diagrams, database instances, queries, results of queries.

The visual representation made possible by a diagram expresses a functional relationship between concepts represented and symbols/connections representing them. e.g., in the diagrammatic representation of Entity Relationship schemas, a rectangle is associated to an entity, a diamond is associated to a relationship.

When drawing a diagram, human beings and display devices adopt suitable drawing conventions, aesthetic...

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Recommended Reading

  1. 1.
    Cruz IF, Tamassia R. Graph drawing tutorial. http://www.cs.brown.edu/~rt/
  2. 2.
    Di Battista G, Eades P, Tamassia R, Tollis IG. Graph drawing. Englewood Cliffs: Prentice-Hall; 1999.zbMATHGoogle Scholar
  3. 3.
    Tufte ER. The visual display of quantitative information. Cheshire: Graphic Press; 1998.Google Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.University of Milano-BicoccaMilanItaly

Section editors and affiliations

  • Tiziana Catarci
    • 1
  1. 1.Dept. di Ingegneria Informatica, Automatica e GestionaleUniversita di RomaRomaItaly