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

Query processing in PIOS

Rabitti F;
1999

Abstract

An approach to query processing in object-oriented stores supporting physical data independence is proposed in this Chapter. In particular, the problem of query optimisation (i e finding efficient execution plans for declarative queries) is investigated. A set of rewrite rules has been defined in order to allow an algebraic optimisation phase. A local search procedure, based on a cost model of the store, has been tailored to the task of physical optimisation. To support the physical data independence in the store, a translation algorithm, dealing with the actual storage organisation of the database, has been studied. A comprehensive example illustrates these mechanisms. Finally, performance results are presented.
1999
Istituto di Scienza e Tecnologie dell'Informazione "Alessandro Faedo" - ISTI
3-540-65772-X
Query processing
PIOS
Physically independent object server
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.14243/387867
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