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Multiple Materialized View Selection for XPath Query Rewriting

by Nan Tang, M. Tamer Özsu, Byron Choi, Kam-fai Wong
"... Abstract — We study the problem of answering XPATH queries using multiple materialized views. Despite the efforts on answering queries using single materialized view, answering queries using multiple views remains relatively new. We address two important aspects of this problem: multiple-view select ..."
Abstract - Cited by 30 (1 self) - Add to MetaCart
Abstract — We study the problem of answering XPATH queries using multiple materialized views. Despite the efforts on answering queries using single materialized view, answering queries using multiple views remains relatively new. We address two important aspects of this problem: multiple

Answering Queries Using Views: A Survey

by Alon Y. Halevy , 2000
"... The problem of answering queries using views is to find efficient methods of answering a query using a set of previously defined materialized views over the database, rather than accessing the database relations. The problem has recently received significant attention because of its relevance to a w ..."
Abstract - Cited by 562 (32 self) - Add to MetaCart
wide variety of data management problems. In query optimization, finding a rewriting of a query using a set of materialized views can yield a more efficient query execution plan. To support the separation of the logical and physical views of data, a storage schema can be described using views over

Answering queries using views

by Alon Y. Levy, Alberto O. Mendelzon, Yehoshua Sagiv, Divesh Srivastava - In PODS Conference , 1995
"... We consider the problem of computing answers to queries by using materialized views. Aside from its potential in optimizing query evaluation, the problem also arises in applications such as Global Information Systems, Mobile Computing and maintaining physical data independence. We consider the probl ..."
Abstract - Cited by 447 (32 self) - Add to MetaCart
the problem of nding a rewriting of a query that uses the materialized views, the problem of nding minimal rewritings, and nding complete rewritings (i.e., rewritings that use only the views). We show that all the possible rewritings can be obtained by considering containment mappings from the views

Efficient algorithms for processing XPath queries

by Georg Gottlob, Christoph Koch, Reinhard Pichler - In VLDB , 2002
"... Our experimental analysis of several popular XPath processors reveals a striking fact: Query evaluation in each of the systems requires time exponential in the size of queries in the worst case. We show that XPath can be processed much more efficiently, and propose main-memory algorithms for this pr ..."
Abstract - Cited by 306 (23 self) - Add to MetaCart
Our experimental analysis of several popular XPath processors reveals a striking fact: Query evaluation in each of the systems requires time exponential in the size of queries in the worst case. We show that XPath can be processed much more efficiently, and propose main-memory algorithms

On Rewriting XPath Queries Using Views

by Foto Afrati, Benny Kimelfeld, Rada Chirkova, Vassia Pavlaki, Manolis Gergatsoulis, Yehoshua Sagiv
"... The problem of rewriting a query using a materialized view is studied for a well known fragment of XPath that includes the following three constructs: wildcards, descendant edges and branches. In earlier work, determining the existence of a rewriting was shown to be coNP-hard, but no tight complexit ..."
Abstract - Cited by 5 (1 self) - Add to MetaCart
The problem of rewriting a query using a materialized view is studied for a well known fragment of XPath that includes the following three constructs: wildcards, descendant edges and branches. In earlier work, determining the existence of a rewriting was shown to be coNP-hard, but no tight

Rewriting XPath Queries Using Materialized Views

by Wanhong Xu, Meral Ozsoyoglu - In VLDB , 2005
"... As a simple XML query language but with enough expressive power, XPath has become very popular. To expedite evaluation of XPath queries, we consider the problem of rewriting XPath queries using materialized XPath views. This problem is very important and arises not only from query optimization in se ..."
Abstract - Cited by 54 (0 self) - Add to MetaCart
As a simple XML query language but with enough expressive power, XPath has become very popular. To expedite evaluation of XPath queries, we consider the problem of rewriting XPath queries using materialized XPath views. This problem is very important and arises not only from query optimization

Rewriting Regular XPath Queries on XML Views

by Wenfei Fan, Floris Geerts, Xibei Jia Anastasios Kementsietsidis - In Proc. ICDE , 2007
"... We study the problem of answering queries posed on virtual views of XML documents, a problem commonly encountered when enforcing XML access control and integrating data. We approach the problem by rewriting queries on views into equivalent queries on the underlying document, and thus avoid the overh ..."
Abstract - Cited by 37 (3 self) - Add to MetaCart
the overhead of view materialization and maintenance. We consider possibly recursively defined XML views and study the rewriting of both XPath and regular XPath queries. We show that while rewriting is not always possible for XPath over recursive views, it is for regular XPath; however, the rewritten query may

� SMOQE is able to rewrite any Regular XPath query �

by Wenfei Fan, Floris Geerts, Xibei Jia, Anastasios Kementsietsidis
"... Abstract: XML views have been widely used to enforce access control, support data integration, and speed up query answering. In many applications, e.g., XML security enforcement, it is prohibitively expensive to materialize and maintain a large number of views. Therefore, views are necessarily virtu ..."
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virtual. This demo presents SMOQE, the first system to provide efficient support for answering queries over virtual and possibly recursively defined XML views. We demonstrate a set of novel techniques for the specification of views, the rewriting, evaluation and optimization of XML queries. Moreover, we

Accelerating XPath location steps

by Torsten Grust - ACM SIGMOD Int. Conference on Management of Data , 2002
"... This work is a proposal for a database index structure that has been specifically designed to support the evaluation of XPath queries. As such, the index is capable to support all XPath axes (including ancestor, following, precedingsibling, descendant-or-self, etc.). This feature lets the index stan ..."
Abstract - Cited by 261 (18 self) - Add to MetaCart
This work is a proposal for a database index structure that has been specifically designed to support the evaluation of XPath queries. As such, the index is capable to support all XPath axes (including ancestor, following, precedingsibling, descendant-or-self, etc.). This feature lets the index

Secure Querying of Recursive XML Views: A Standard XPath-based Technique ∗

by Houari Mahfoud, Abdessamad Imine , 2012
"... Most state-of-the art approaches for securing XML documents allow users to access data only through authorized views defined by annotating an XML grammar (e.g. DTD) with a collection of XPath expressions. To prevent improper disclosure of confidential information, user queries posed on these views n ..."
Abstract - Cited by 1 (1 self) - Add to MetaCart
need to be rewritten into equivalent queries on the underlying documents, which enables us to avoid theoverhead ofview materialization and maintenance. A major concern here is that XPath query rewriting for recursive XML views is still an open problem. To overcome this problem, some authors have
Results 1 - 10 of 1,836