article

XML tree structure compression using RePair

Authors:

Sebastian Maneth,

Roy MennickeAuthors Info & Claims

Information Systems, Volume 38, Issue 8

Pages 1150 - 1167

https://doi.org/10.1016/j.is.2013.06.006

Published: 01 November 2013 Publication History

Abstract

XML tree structures can conveniently be represented using ordered unranked trees. Due to the repetitiveness of XML markup these trees can be compressed effectively using dictionary-based methods, such as minimal directed acyclic graphs (DAGs) or straight-line context-free (SLCF) tree grammars. While minimal SLCF tree grammars are in general smaller than minimal DAGs, they cannot be computed in polynomial time unless P=NP. Here, we present a new linear time algorithm for computing small SLCF tree grammars, called TreeRePair, and show that it greatly outperforms the best known previous algorithm BPLEX. TreeRePair is a generalization to trees of Larsson and Moffat's RePair string compression algorithm. SLCF tree grammars can be used as efficient memory representations of trees. Using TreeRePair, we are able to produce the smallest queryable memory representation of ordered trees that we are aware of. Our investigations over a large corpus of commonly used XML documents show that tree traversals over TreeRePair grammars are 14 times slower than over pointer structures and 5 times slower than over succinct trees, while memory consumption is only 1/43 and 1/6, respectively. With respect to file compression we are able to show that a Huffman-based coding of TreeRePair grammars gives compression ratios comparable to the best known XML file compressors.

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Cited By

Lohrey MSchmid M(2024)Enumeration for MSO-Queries on Compressed TreesProceedings of the ACM on Management of Data10.1145/36511412:2(1-17)Online publication date: 14-May-2024
https://dl.acm.org/doi/10.1145/3651141
Guan JZhang FMa SChen KHu YChen YPan ADu X(2023)Homomorphic Compression: Making Text Processing on Compression UnlimitedProceedings of the ACM on Management of Data10.1145/36267651:4(1-28)Online publication date: 12-Dec-2023
https://dl.acm.org/doi/10.1145/3626765
Chen ZZhang FGuan JZhai JShen XZhang HShu WDu X(2023)CompressGraph: Efficient Parallel Graph Analytics with Rule-Based CompressionProceedings of the ACM on Management of Data10.1145/35886841:1(1-31)Online publication date: 30-May-2023
https://dl.acm.org/doi/10.1145/3588684
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Index Terms

XML tree structure compression using RePair
1. Mathematics of computing
  1. Discrete mathematics
    1. Graph theory
      1. Trees

Index terms have been assigned to the content through auto-classification.

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cover image Information Systems

Information Systems Volume 38, Issue 8

November, 2013

278 pages

ISSN:0306-4379

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Copyright © Elsevier Ltd © 2013.

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Elsevier Science Ltd.

United Kingdom

Publication History

Published: 01 November 2013

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Cited By

Lohrey MSchmid M(2024)Enumeration for MSO-Queries on Compressed TreesProceedings of the ACM on Management of Data10.1145/36511412:2(1-17)Online publication date: 14-May-2024
https://dl.acm.org/doi/10.1145/3651141
Guan JZhang FMa SChen KHu YChen YPan ADu X(2023)Homomorphic Compression: Making Text Processing on Compression UnlimitedProceedings of the ACM on Management of Data10.1145/36267651:4(1-28)Online publication date: 12-Dec-2023
https://dl.acm.org/doi/10.1145/3626765
Chen ZZhang FGuan JZhai JShen XZhang HShu WDu X(2023)CompressGraph: Efficient Parallel Graph Analytics with Rule-Based CompressionProceedings of the ACM on Management of Data10.1145/35886841:1(1-31)Online publication date: 30-May-2023
https://dl.acm.org/doi/10.1145/3588684
Diekert VFernau HWolf P(2022)Properties of graphs specified by a regular languageActa Informatica10.1007/s00236-022-00427-z59:4(357-385)Online publication date: 1-Aug-2022
https://dl.acm.org/doi/10.1007/s00236-022-00427-z
Ganardi MJeż ALohrey M(2021)Balancing Straight-line ProgramsJournal of the ACM10.1145/345738968:4(1-40)Online publication date: 30-Jun-2021
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Hucke DLohrey MBenkner L(2021)Entropy Bounds for Grammar-Based Tree CompressorsIEEE Transactions on Information Theory10.1109/TIT.2021.311267667:11(7596-7615)Online publication date: 1-Nov-2021
https://dl.acm.org/doi/10.1109/TIT.2021.3112676
Bannai HHirayama MHucke DInenaga SJeż ALohrey MReh C(2021)The Smallest Grammar Problem RevisitedIEEE Transactions on Information Theory10.1109/TIT.2020.303814767:1(317-328)Online publication date: 1-Jan-2021
https://dl.acm.org/doi/10.1109/TIT.2020.3038147
Casel KFernau HGaspers SGras BSchmid M(2021)On the Complexity of the Smallest Grammar Problem over Fixed AlphabetsTheory of Computing Systems10.1007/s00224-020-10013-w65:2(344-409)Online publication date: 1-Feb-2021
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Diekert VFernau HWolf P(2021)Properties of Graphs Specified by a Regular LanguageDevelopments in Language Theory10.1007/978-3-030-81508-0_10(117-129)Online publication date: 16-Aug-2021
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Gascón ALohrey MManeth SReh CSieber K(2020)Grammar-Based Compression of Unranked TreesTheory of Computing Systems10.1007/s00224-019-09942-y64:1(141-176)Online publication date: 1-Jan-2020
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