Article

A normal form for XML documents

Authors:

Marcelo Arenas,

Leonid LibkinAuthors Info & Claims

PODS '02: Proceedings of the twenty-first ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems

Pages 85 - 96

https://doi.org/10.1145/543613.543625

Published: 03 June 2002 Publication History

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Abstract

This paper takes a first step towards the design and normalization theory for XML documents. We show that, like relational databases, XML documents may contain redundant information, and may be prone to update anomalies. Furthermore, such problems are caused by certain functional dependencies among paths in the document. Our goal is to find a way of converting an arbitrary DTD into a well-designed one, that avoids these problems. We first introduce the concept of a functional dependency for XML, and define its semantics via a relational representation of XML. We then define an XML normal form, XNF, that avoids update anomalies and redundancies. We study its properties and show that it generalizes BCNF and a normal form for nested relations when those are appropriately coded as XML documents. Finally, we present a lossless algorithm for converting any DTD into one in XNF.

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Cited By

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Suciu D(2023)Applications of Information Inequalities to Database Theory Problems2023 38th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS)10.1109/LICS56636.2023.10175769(1-30)Online publication date: 26-Jun-2023
https://doi.org/10.1109/LICS56636.2023.10175769
Fan WLu P(2019)Dependencies for GraphsACM Transactions on Database Systems10.1145/328728544:2(1-40)Online publication date: 13-Feb-2019
https://dl.acm.org/doi/10.1145/3287285
Arenas M(2018)XML Integrity ConstraintsEncyclopedia of Database Systems10.1007/978-1-4614-8265-9_787(4756-4761)Online publication date: 7-Dec-2018
https://doi.org/10.1007/978-1-4614-8265-9_787
Show More Cited By

Index Terms

A normal form for XML documents
1. Applied computing
  1. Document management and text processing
    1. Document preparation
      1. Markup languages
2. Information systems
  1. World Wide Web
    1. Web data description languages
      1. Markup languages

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Reviews

Reviewer: Herman Fischer

Arenas and Libkin define the background and requirements of a normal form of Extensible Markup Language (XML), with the goal of converting arbitrary XML into well-formed XML. Since my own work is with Extensible Business Reporting Language (XBRL) processor implementation, this background, and their algorithm for normalizing XML documents, is of high interest to me. Recent database implementations for storing normal-form XML data-both those implemented specifically for XML, such as Apache.org's XIndice, and by XML features added to popular commercial heavyweight relational databases-make this technology timely and of wide interest. The authors begin by demonstrating the need to normalize XML, based on XML data structures that have redundancies of data in different areas of the structure. They relate that to relational functional dependency. Extending from relational to XML functional dependencies, the authors then represent XML tree structured data into tuples (XBRL also does this). Functional dependencies are defined using tree tuples. Finally, an XML normal form (XNF) is defined. Anticipating massive Web databases of poorly organized data, the authors' goal is to provide principles for good design, and algorithms for producing that design, sort of an XML schema reengineering. My take on this process is different: I see the need for this technology in the opposite direction, not for the rescue of Web "stuff," but for the upcoming new generations of databases and software that will all be based on XML technologies. Mainstream business processing now considers XML and XML derivatives for automated interchange between systems, and as core infrastructural technology. Physically, this paper seems to be about the right length (12 pages). The presentation is consistent with the authors' ideas, and the text was easy to read. The latest reference is from one year before publication. This paper demonstrates that XML structure can be converted to a normal form, and that data can be losslessly converted into the resulting structure. In my work with XBRL, there are more expressed semantics than just the structure of data. Source fact values expressed in XML are given context, measure, role restrictions, and semantics, defined in XML linking language (XLink) linkbases. Applications of the authors' theories, if extendable, would be very useful. I would recommend this paper to researchers and developers of XML and XML-derived data structuring and data storing technology. Online Computing Reviews Service

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Published In

PODS '02: Proceedings of the twenty-first ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems

June 2002

311 pages

ISBN:1581135076

DOI:10.1145/543613

Conference Chair:
Lucian Popa
IBM Almaden Research Center
,
General Chair:
Serge Abiteboul
INRIA
,
Program Chair:
Phokion G. Kolaitis
UC Santa Cruz & IBM Almaden Research Center

Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than ACM must be honored. Abstracting with credit is permitted. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from [email protected]

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Association for Computing Machinery

New York, NY, United States

Publication History

Published: 03 June 2002

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SIGMOD/PODS02

Sponsor:

SIGMOD/PODS02: International Conference on Management of Data and Symposium on Principles Database and Systems

June 3 - 5, 2002

Wisconsin, Madison

Acceptance Rates

PODS '02 Paper Acceptance Rate 24 of 109 submissions, 22%;

Overall Acceptance Rate 642 of 2,707 submissions, 24%

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Cited By

View all

Suciu D(2023)Applications of Information Inequalities to Database Theory Problems2023 38th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS)10.1109/LICS56636.2023.10175769(1-30)Online publication date: 26-Jun-2023
https://doi.org/10.1109/LICS56636.2023.10175769
Fan WLu P(2019)Dependencies for GraphsACM Transactions on Database Systems10.1145/328728544:2(1-40)Online publication date: 13-Feb-2019
https://dl.acm.org/doi/10.1145/3287285
Arenas M(2018)XML Integrity ConstraintsEncyclopedia of Database Systems10.1007/978-1-4614-8265-9_787(4756-4761)Online publication date: 7-Dec-2018
https://doi.org/10.1007/978-1-4614-8265-9_787
Fan WLu PSallinger EVan den Bussche JGeerts F(2017)Dependencies for GraphsProceedings of the 36th ACM SIGMOD-SIGACT-SIGAI Symposium on Principles of Database Systems10.1145/3034786.3056114(403-416)Online publication date: 9-May-2017
https://dl.acm.org/doi/10.1145/3034786.3056114
Arenas M(2017)XML Integrity ConstraintsEncyclopedia of Database Systems10.1007/978-1-4899-7993-3_787-2(1-7)Online publication date: 19-Sep-2017
https://doi.org/10.1007/978-1-4899-7993-3_787-2
Karnok DKemény ZIlie-Zudor EMonostori L(2016)Data type definition and handling for supporting interoperability across organizational bordersJournal of Intelligent Manufacturing10.1007/s10845-014-0884-927:1(167-185)Online publication date: 1-Feb-2016
https://dl.acm.org/doi/10.1007/s10845-014-0884-9
Schroeder RDuarte Ddos Santos Mello R(2012)On evaluating an approach for balancing the trade‐off on XML schema designInternational Journal of Web Information Systems10.1108/174400812112828748:4(371-389)Online publication date: 16-Nov-2012
https://doi.org/10.1108/17440081211282874
Bouchou BFerrari MLima M(2011)Attribute grammar for XML integrity constraint validationProceedings of the 22nd international conference on Database and expert systems applications - Volume Part I10.5555/2035368.2035378(94-109)Online publication date: 29-Aug-2011
https://dl.acm.org/doi/10.5555/2035368.2035378
Sali ASchewe K(2011)Weak functional dependencies on trees with restructuringActa Cybernetica10.14232/actacyb.20.2.2011.520:2(285-329)Online publication date: 1-Feb-2011
https://dl.acm.org/doi/10.14232/actacyb.20.2.2011.5
Schroeder RDuarte DMello R(2011)A workload-aware approach for optimizing the XML schema design trade-offProceedings of the 13th International Conference on Information Integration and Web-based Applications and Services10.1145/2095536.2095542(12-19)Online publication date: 5-Dec-2011
https://dl.acm.org/doi/10.1145/2095536.2095542
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