Query Rewriting Based on Meta-Granular Aggregation.
Piotr Wiśniewski, Krzysztof Stencel · 2013
Abstract. Analytical database queries are exceptionally time consuming. Decision support systems employ various execution techniques in order to accelerate such queries and reduce their resource consumption. Probably the most important of them consists in materialization of partial results. However, any introduction of additional derived objects into the database schema increases the cost of software development, since programmers must take care of their usage and synchronization. In this paper we propose novel query rewriting methods that build queries using partial aggregations materialized in additional tables. These methods are based on the concept of meta-granules that represent the information on grouping and used aggregations. Meta-granules have a natural partial order that guides the optimisation process. We also present an experimental evaluation of the proposed rewriting method. 1