Encyclopedia of Database Systems

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

Event in Active Databases

  • AnnMarie Ericsson
  • Mikael Berndtsson
  • Jonas Mellin
Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-8265-9_512

Definition

Events in active databases are typically considered to be atomic and instantaneous, that is, they either happen or not. Events are either primitive or composite, that is, either they are part of the system (primitive) or they are specified in terms of other events (composite).

Key Points

An event is a happening of interest that can invoke execution of reactive behavior, for example, trigger an ECA rule. Events in active databases are typically considered to be atomic and instantaneous [1, 3, 4], that is, they either happen or not. However, this leads to problems [2] addressed in the event specification entry.

Events can be classified as primitive or composite events. Primitive events refer to elementary occurrences that are predefined in the system. Primitive events are typically further categorized as database events, time events, transaction events, method events, etc. A composite event is a set of events matching an event specification.

Events can have attributes, that...

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Recommended Reading

  1. 1.
    Chakravarthy S, Mishra D. Snoop: an expressive event specification language for active databases. Data Knowl Eng. 1994;14(1):1–26.CrossRefGoogle Scholar
  2. 2.
    Galton A, Augusto J. Two approaches to event definition. In: Proceedings of the 13th International Conference on Database and Expert System Application; 2002. p. 547–56.Google Scholar
  3. 3.
    Gatziu S. Events in an active object-oriented database system. PhD thesis, University of Zurich, Switzerland. 1994.Google Scholar
  4. 4.
    Gehani N, Jagadish HV, Smueli O. Event specification in an active object-oriented database. In: Proceedings of the ACM SIGMOD International Conference on Management of Data; 1992. p. 81–90.Google Scholar

Copyright information

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

Authors and Affiliations

  • AnnMarie Ericsson
    • 1
  • Mikael Berndtsson
    • 2
    • 3
  • Jonas Mellin
    • 2
    • 3
  1. 1.University of SkövdeSkövdeSweden
  2. 2.University of Skövde, The Informatics Research CentreSkövdeSweden
  3. 3.University of Skövde, School of InformaticsSkövdeSweden

Section editors and affiliations

  • M. Tamer Özsu
    • 1
  1. 1.Cheriton School of Computer ScienceUniversity of WaterlooWaterlooCanada