Main Memory Implementations for Binary Grouping

  • Norman May
  • Guido Moerkotte
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3671)


An increasing number of applications depend on efficient storage and analysis features for XML data. Hence, query optimization and efficient evaluation techniques for the emerging XQuery standard become more and more important. Many XQuery queries require nested expressions. Unnesting them often introduces binary grouping.

We introduce several algorithms implementing binary grouping and analyze their time and space complexity. Experiments demonstrate their performance.


Space Complexity Hash Table Pseudo Code Binary Search Tree Aggregate Function 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • Norman May
    • 1
  • Guido Moerkotte
    • 1
  1. 1.University of MannheimMannheimGermany

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