Special Databases
Temporal Databases
<Back to Themes & Resources page>
- While a standard database collects data about the current state of a set of entities, a temporal database includes data about entities that evolve over time. When an entity changes, its new state is recorded but the former state is kept in the temporal database. As a consequence, it is possible to rebuild the state of the application domain at a certain time point. It is also possible to extract the evolution of a set of entities during a certain period. A fully temporal database records the past, current and future states of entities. One considers two types of time. The transaction (or physical) time indicates when data have been recorded, changes and deleted in the database. The valid (or logical) time indicates when events occurs in the application domain. A bitemporal database record both types of time.
- A short introduction to temporal databases can be found in book [B09], appendix C. Reference [B02-01] includes a more detailed description of how temporal data are represented, managed and queried. The code of a temporal database implemented as an active database is described and discussed in detail. Reference [P01-02] develops a hierarchy of temporal data models, a design methodology and a CASE tool for temporal databases engineering. The Quetelet software includes a temporal database storing historical statistics [P07-05].
- temporal database, active database, statistical database
- [B09] Jean-Luc Hainaut. Bases de données - Concepts, utilisation et développement, Dunod, Collection Sciences Sup, Paris, 2009. [book description]
- [P07-05] Detienne V., Vesentini F., Hainaut J-L., Entreposage et exploitation de documents multidimensionnels évolutifs : le cas des tableaux statistiques, in Document Numérique, numéro spécial Entreposage de documents et données semi-structurées, Hermès, 2007 [full text]
- [B02-01] Jean-Luc Hainaut, Virginie Detienne. Introduction pratique aux bases de données temporelles novembre 2002, 116 pages. [full text]
- [P01-02] Virginie Detienne and Jean-Luc Hainaut. CASE Tool Support for Temporal Database Design, in Proceedings of the 20th International Conference on Conceptual modeling, (ER’01), Lecture Notes in Computer Science, Volume 2224, pages 208-224, Springer-Verlag, 2001. [description] [full text]
<Back to Themes & Resources page>