Selecting and Using Views to Compute Aggregate Queries (Extended Abstract)

d abstract) Foto Afrati1 and Rada Chirkova2 1 Electrical and Computing Eng., National Technical University of Athens, 157 73 Athens, Greece 2 Computer Science Department, North Carolina State University, Raleigh, NC 27695, USA We consider a workload of aggregate queries and investigate the problem of selecting views that (1) provide equivalent rewritings for all queries, and (2) are optimal, in that the cost of evaluating the query workload is minimized. We consider conjunctive views and rewritings, with or without aggregation; in each rewriting, only one view contributes to computing the aggregated query output. We look at query rewriting using existing views and at view selection. In the query-rewriting problem, we give sufficient and necessary conditions for a rewriting to exist. For view selection, we prove complexity results. Finally, we give algorithms for obtaining rewritings and selecting views.

• Type: Conference
• Year: 2005
• Where: ICDT
• Authors: Foto N. Afrati, Rada Chirkova
• Keywords: Database, ICDT 2005, National Technical University Of Athens, North Carolina State University, View Selection