Files in this item



application/pdfEfficient Proce ... regate Queries in OLAP.pdf (239kB)
(no description provided)PDF


Title:Efficient Processing of Ad-Hoc Top-k Aggregate Queries in OLAP
Author(s):Li, Chengkai; Chang, Kevin Chen-Chuan; Ilyas, Ihab F.
Subject(s):Web search; database systems
Abstract:In this paper, we develop a principled framework for efficient processing of ad-hoc top-k (ranking) aggregate queries in OLAP. Such queries provide the k groups with the highest aggregates to decision makers. Essential support of top-k aggregate queries is lacking in current RDBMSs, which process such queries in a naive and overkill materialize- group-sort scheme, therefore can be prohibitively inefficient. Our new framework is based on two fundamental properties, the Group-Ranking and Tuple-Ranking Principles. The principles dictate group-ordering and tuple-ordering requirement that together guide the query processor toward the optimal aggregate query processing. To realize the requirements, we propose a new execution model and address the challenges of implementing new query operators, enabling efficient top-k aggregate query plans that are both group- aware and rank-aware. The experimental study validates our framework by demonstrating orders of magnitude performance improvement in the new query plans, compared with the traditional approach.
Issue Date:2005-06
Genre:Technical Report
Other Identifier(s):UIUCDCS-R-2005-2596
Rights Information:You are granted permission for the non-commercial reproduction, distribution, display, and performance of this technical report in any format, BUT this permission is only for a period of 45 (forty-five) days from the most recent time that you verified that this technical report is still available from the University of Illinois at Urbana-Champaign Computer Science Department under terms that include this permission. All other rights are reserved by the author(s).
Date Available in IDEALS:2009-04-20

This item appears in the following Collection(s)

Item Statistics