Exploiting Constraints in Query Processing

Junhu Wang

ISBN 10: 3838331508 / ISBN 13: 9783838331508

Published by LAP LAMBERT Academic Publishing Sep 2010, 2010

About this Item

This item is printed on demand - Print on Demand Titel. Neuware -This book focuses on the optimization of general conjunctive queries (GCQ) using integrity constraints and in the presence of materialized views. A GCQ is a conjunctive query with arbitrary built-in predicates. The integrity constraints we consider are disjunctive constrained tuple- generating dependencies (DCTGDs)which include many traditional integrity constraints such as functional dependencies, inclusion dependencies, and constrained tuple-generating dependencies. We first present an improved method for testing general conjunctive query containment using relevance mappings. We then present a method for testing general conjunctive query containment in the presence of DCTGDs. Our method generalizes and improves previous algorithms for the semantic containment problem of conjunctive queries. When materialized views exist, we study the problem of rewriting a union of general conjunctive queries using the view relations under the open world assumption and present a general approach for such problems. Our approach can rewrite unions of general conjunctive queries when both the query and the views involve built-in predicates.Books on Demand GmbH, Überseering 33, 22297 Hamburg 212 pp. Englisch.

Seller Inventory # 9783838331508

Bibliographic Details

• Title: Exploiting Constraints in Query Processing
• Publisher: LAP LAMBERT Academic Publishing Sep 2010
• Publication Date: 2010
• Language: English
• ISBN 10: 3838331508
• ISBN 13: 9783838331508
• Binding: Taschenbuch
• Condition: Neu
• Dimensions: 220W x 150H x 14D millimeters 220 millimeters width by 150 millimeters height by 14 millimeters depth
• Weight: 334 grams

About this title

Synopsis

This book focuses on the optimization of general conjunctive queries (GCQ) using integrity constraints and in the presence of materialized views. A GCQ is a conjunctive query with arbitrary built-in predicates. The integrity constraints we consider are disjunctive constrained tuple- generating dependencies (DCTGDs)which include many traditional integrity constraints such as functional dependencies, inclusion dependencies, and constrained tuple-generating dependencies. We first present an improved method for testing general conjunctive query containment using relevance mappings. We then present a method for testing general conjunctive query containment in the presence of DCTGDs. Our method generalizes and improves previous algorithms for the semantic containment problem of conjunctive queries. When materialized views exist, we study the problem of rewriting a union of general conjunctive queries using the view relations under the open world assumption and present a general approach for such problems. Our approach can rewrite unions of general conjunctive queries when both the query and the views involve built-in predicates.