Evaluating queries with generalized path expressions

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Abstract

In the past few years, query languages featuring generalized path expressions have been proposed. These languages allow the interrogation of both data and structure. They are powerful and essential for a number of applications. However, until now, their evaluation has relied on a rather naive and inefficient algorithm.In this paper, we extend an object algebra with two new operators and present some interesting rewriting techniques for queries featuring generalized path expressions. We also show how a query optimizer can integrate the new techniques.

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Evaluating queries with generalized path expressions

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cover image ACM SIGMOD Record

ACM SIGMOD Record Volume 25, Issue 2 ISSN: 0163-5808 DOI: 10.1145/235968

cover image ACM Conferences

SIGMOD '96: Proceedings of the 1996 ACM SIGMOD international conference on Management of data ISBN: 0897917944 DOI: 10.1145/233269 Copyright © 1996 ACM.

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