Query Processing in PIOS

  • Fausto Rabitti
  • Leonardo Benedetti
  • Federico Demi
Conference paper
Part of the Workshops in Computing book series (WORKSHOPS COMP.)


An approach to query processing in object-oriented stores supporting physical data independence is proposed in this paper. In particular, the problem of query optimization (i.e. finding efficient execution plans for declarative queries) has been investigated. A set of rewrite rules has been defined in order to allow an algebraic optimization phase. A local search procedure, based on a cost model of the store, has been tailored to the task of physical optimization. To support the physical data independence in the store, a translation algorithm, dealing with the actual storage organization of the database, has been studied. A comprehensive example illustrates these mechanisms. Finally, performance results are presented.


Query Processing Query Language Query Optimization Local Search Procedure Storage Schema 
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

© British Computer Society 1995

Authors and Affiliations

  • Fausto Rabitti
    • 1
  • Leonardo Benedetti
    • 1
  • Federico Demi
    • 1
  1. 1.IEI-CNRPisaItaly

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