Database Querying under Changing Preferences

Jan Chomicki

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arXiv · cs/0607013

Database Querying under Changing Preferences

Jan Chomicki

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Abstract

We present here a formal foundation for an iterative and incremental approach to constructing and evaluating preference queries. Our main focus is on query modification: a query transformation approach which works by revising the preference relation in the query. We provide a detailed analysis of the cases where the order-theoretic properties of the preference relation are preserved by the revision. We consider a number of different revision operators: union, prioritized and Pareto composition. We also formulate algebraic laws that enable incremental evaluation of preference queries. Finally, we consider two variations of the basic framework: finite restrictions of preference relations and weak-order extensions of strict partial order preference relations.

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Jan Chomicki. 2006-07-05. Database Querying under Changing Preferences. https://arxiv.org/abs/cs/0607013

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