Results 21 - 30
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111
System RX: one part relational, one part XML
- in: Proceedings of ACM SIGMOD International Conference on Management of Data, 2005
"... This paper describes the overall architecture and design aspects of a hybrid relational and XML database system called System RX. We believe that such a system is fundamental in the evolution of enterprise data management solutions: XML and relational data will co-exist and complement each other in ..."
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Cited by 17 (0 self)
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This paper describes the overall architecture and design aspects of a hybrid relational and XML database system called System RX. We believe that such a system is fundamental in the evolution of enterprise data management solutions: XML and relational data will co-exist and complement each other in enterprise solutions. Furthermore, a successful XML repository requires much of the same infrastructure that already exists in a relational database management system. Finally, XML query languages have con-siderable conceptual and functional overlap with relational data-flow engines. System RX is the first truly hybrid system that co-mingles XML and relational data, giving them equal footing. The new support for XML includes native support for storage and indexing as well as query compilation and evaluation support for the latest industry-standard query languages, SQL/XML and XQuery. By building a hybrid system, we leverage more than 20 years of data management research to advance XML technology to the same standards expected from mature relational systems. 1.
ArchIS: an XML-based approach to transaction-time temporal . . .
- THE VLDB JOURNAL
"... Effective support for temporal applications by database systems represents an important technical objective that is difficult to achieve since it requires an integrated solution for several problems, including (i) expressive temporal representations and data models, (ii) powerful languages for temp ..."
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Cited by 16 (11 self)
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Effective support for temporal applications by database systems represents an important technical objective that is difficult to achieve since it requires an integrated solution for several problems, including (i) expressive temporal representations and data models, (ii) powerful languages for temporal queries and snapshot queries, (iii) indexing, clustering and query optimization techniques for managing temporal information efficiently, and (iv) architectures that bring together the different pieces of enabling technology into a robust system. In this paper, we present the ArchIS system that achieves these objectives by supporting a temporally grouped data model on top of RDBMS. ArchIS ’ architecture uses (a) XML to support temporally grouped (virtual) representations of the database history, (b) XQuery to express powerful temporal queries on such views, (c) temporal clustering and indexing techniques for managing the actual historical data in a relational database, and (d) SQL/XML for executing the queries on the XML views as equivalent queries on the relational database. The performance studies presented in the paper show that ArchIS is quite effective at storing and retrieving under complex query conditions the transaction-time history of relational databases, and can also
Pattern Tree Algebras: Sets Or Sequences?
, 2005
"... XML and XQuery semantics are very sensitive to the order of the produced output. Although pattern-tree based algebraic approaches are becoming more and more popular for evaluating XML, there is no universally accepted technique which can guarantee both a correct output order and a choice of ef ..."
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Cited by 16 (2 self)
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XML and XQuery semantics are very sensitive to the order of the produced output. Although pattern-tree based algebraic approaches are becoming more and more popular for evaluating XML, there is no universally accepted technique which can guarantee both a correct output order and a choice of efficient alternative plans.
Destabilizers and Independence of XML Updates
"... Independence analysis is the problem of determining whether an update affects the result of a query, e.g. a constraint or materialized view. We develop a new, modular framework for static independence analysis that decomposes the problem into two orthogonal subproblems: approximating the destabilize ..."
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Cited by 15 (1 self)
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Independence analysis is the problem of determining whether an update affects the result of a query, e.g. a constraint or materialized view. We develop a new, modular framework for static independence analysis that decomposes the problem into two orthogonal subproblems: approximating the destabilizer, that is, a finite representation of the set of updates that can change the result of the query, and testing whether the update and destabilizer overlap via an intersection analysis. Focusing on XML queries as the view language and the XQuery Update Facility as the update language, we present a syntactic query rewriting algorithm for translating queries to destabilizers, and show that intersection checking can be reduced to satisfiability problems for which efficient checkers already exist. We present an implementation based on an expressive tree satisfiability checker and a Satisfiability Modulo Order package, and give experiments confirming that the resulting analysis is both fast and effective. 1.
Query Translation from XPath to SQL in the Presence of Recursive DTDs
- In VLDB
, 2005
"... The interaction between recursion in XPATH and recursion in DTDs makes it challenging to answer XPATH queries on XML data that is stored in an RDBMS via schema-based shredding. We present a new approach to translating XPATH queries into SQL queries with a simple least fixpoint (LFP) operator, ..."
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Cited by 13 (1 self)
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The interaction between recursion in XPATH and recursion in DTDs makes it challenging to answer XPATH queries on XML data that is stored in an RDBMS via schema-based shredding. We present a new approach to translating XPATH queries into SQL queries with a simple least fixpoint (LFP) operator, which is already supported by most commercial RDBMS. The approach is based on our algorithm for rewriting XPATH queries into regular XPATH expressions, which are capable of capturing both DTD recursion and XPATH queries in a uniform framework. Furthermore, we provide an algorithm for translating regular XPATH queries to SQL queries with LFP, and optimization techniques for minimizing the use of the LFP operator.
The pq-Gram Distance between Ordered Labeled Trees
- ACM TRANSACTIONS ON DATABASE SYSTEMS (TODS)
, 2010
"... When integrating data from autonomous sources, exact matches of data items that represent the same real world object often fail due to a lack of common keys. Yet in many cases structural information is available and can be used to match such data. Typically the matching must be approximate since the ..."
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Cited by 13 (5 self)
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When integrating data from autonomous sources, exact matches of data items that represent the same real world object often fail due to a lack of common keys. Yet in many cases structural information is available and can be used to match such data. Typically the matching must be approximate since the representations in the sources differ. We propose pq-grams to approximately match hierarchical data from autonomous sources and define the pq-gram distance between ordered labeled trees as an effective and efficient approximation of the fanout weighted tree edit distance. We prove that the pq-gram distance is a lower bound of the fanout weighted tree edit distance and give a normalization of the pq-gram distance for which the triangle inequality holds. Experiments on synthetic and real world data (residential addresses and XML) confirm the scalability of our approach and show the effectiveness of pq-grams.
Survey over Existing Query and Transformation Languages -- Revision 2.0
, 2006
"... A widely acknowledged obstacle for realizing the vision of the Semantic Web is the inability of many current Semantic Web approaches to cope with data available in such diverging representation formalisms as XML, RDF, or Topic Maps. A common query language is the first step to allow transparent acce ..."
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Cited by 12 (5 self)
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A widely acknowledged obstacle for realizing the vision of the Semantic Web is the inability of many current Semantic Web approaches to cope with data available in such diverging representation formalisms as XML, RDF, or Topic Maps. A common query language is the first step to allow transparent access to data in any of these formats. To further the understanding of the requirements and approaches proposed for query languages in the conventional as well as the Semantic Web, this report surveys a large number of query languages for accessing XML, RDF, or Topic Maps. This is the first systematic survey to consider query languages from all these areas. From the detailed survey of these query languages, a common classification scheme is derived that is useful for understanding and differentiating languages within and among all three areas. This revision of deliverable I4-D1 extends that deliverable by a refined version of the presented material that has been published as a chapter in the LNCS tutorial volume for the REWERSE “Reasoning Web ” 2005 summer school as well as short outlooks on further refinements of the material for upcoming tutorials
UXQuery: building updatable XML views over relational databases
- In Simpósio Brasileiro de Banco de Dados, SBBD
, 2003
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Using XML to Build Efficient Transaction-Time Temporal Database Systems
- In Proc. of ICDE 2006
, 2005
"... Better support for temporal applications by database systems represents an important technical objective that is di#cult to achieve since it requires integrated solutions for technical problems that are challenging on their own, including (i) expressive temporal representations and data models ..."
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Cited by 10 (4 self)
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Better support for temporal applications by database systems represents an important technical objective that is di#cult to achieve since it requires integrated solutions for technical problems that are challenging on their own, including (i) expressive temporal representations and data models, (ii) powerful languages for temporal queries and snapshot queries, (iii) indexing, clustering and query optimization techniques for managing temporal information e#ciently, and (iv) architectures that bring together the di#erent pieces of enabling technology into a robust system.
DB2 goes hybrid: Integrating native XML and XQuery with relational data and SQL
- IBM Systems Journal
"... Comprehensive and efficient support for XML data management is a rapidly increasing requirement for database systems. To address this requirement, DB2 Universal Databasee (UDB) now combines relational data management with native XML support. This makes DB2t a truly hybrid database management system ..."
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Cited by 8 (1 self)
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Comprehensive and efficient support for XML data management is a rapidly increasing requirement for database systems. To address this requirement, DB2 Universal Databasee (UDB) now combines relational data management with native XML support. This makes DB2t a truly hybrid database management system with first-class support for both XML and relational data processing as well as the integration of the two. This paper presents the overall architecture and design aspects of native XML support in DB2 UDB and its integration with the relational data-flow engine. We describe the new XML components in DB2 UDB and show how XML processing leverages much of the infrastructure which is used for relational data.
