Evaluation and improvement of query processing methods in wide and local area network

An accurate cost model of query processing, designed for distributed conventional query optimizers in an extensible database, is introduced. The model can also be used by extensible query optimizers, namely in select-project-join queries. The cost model is used for qualitative comparison of the effectiveness of distributed query processing strategies as a function of relation sizes and joining attribute selectivity factors. The analysis is performed for both local and wide area networks.<
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