Building Adaptive Applications using Active Mediators

  • Tore Risch
  • Gio Wiederhold
Conference paper


We extend current DBMS technology to support applications in dynamic and heterogenous environments. Our approach raises the level of software support available from DBMSs to include an intermediate layer of software to mediate between databases and their use by applications and users. In particular we are demonstrating active mediators, where the application instructs a mediator to actively monitor databases for change in information that the application depends on. We identify how mediators can support applications that are sensitive to change.

A prototype platform for these classes of mediators has been developed. As a uniform interface language throughout the system we use OSQL, a declarative object-oriented query language. OSQL statements are optimized using concepts extracted from Datalog and relational database research.


Main Memory Query Language Task Model Tracking Procedure Persistent Data 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Wien 1991

Authors and Affiliations

  • Tore Risch
    • 1
  • Gio Wiederhold
    • 2
  1. 1.Hewlett-Packard LaboratoriesPalo AltoUSA
  2. 2.Department of Computer ScienceStanford UniversityStanfordUSA

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