Abstract
The basic planner of Chap. 10 uses a simple algorithm to create its query plans. Unfortunately, those plans often entail significantly more block accesses than needed, for two basic reasons: the operations are performed in a suboptimal order, and they do not take advantage of the indexed, materialized, or multibuffer implementations of Chaps. 12–14. This chapter examines how the planner can address these problems and generate efficient plans. This task is called query optimization. The most efficient plan for a query can be several orders of magnitude faster than a naïve plan, which is the difference between a database engine that can respond to queries in a reasonable amount of time and a database engine that is completely unusable.
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Sciore, E. (2020). Query Optimization. In: Database Design and Implementation. Data-Centric Systems and Applications. Springer, Cham. https://doi.org/10.1007/978-3-030-33836-7_15
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DOI: https://doi.org/10.1007/978-3-030-33836-7_15
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