JavaML: a markup language for Java source code
Proceedings of the 9th international World Wide Web conference on Computer networks : the international journal of computer and telecommunications netowrking
Accelerating XPath location steps
Proceedings of the 2002 ACM SIGMOD international conference on Management of data
Holistic twig joins: optimal XML pattern matching
Proceedings of the 2002 ACM SIGMOD international conference on Management of data
WISE '02 Proceedings of the 3rd International Conference on Web Information Systems Engineering
XPath queries on streaming data
Proceedings of the 2003 ACM SIGMOD international conference on Management of data
Efficient algorithms for processing XPath queries
VLDB '02 Proceedings of the 28th international conference on Very Large Data Bases
XMark: a benchmark for XML data management
VLDB '02 Proceedings of the 28th international conference on Very Large Data Bases
Staircase join: teach a relational DBMS to watch its (axis) steps
VLDB '03 Proceedings of the 29th international conference on Very large data bases - Volume 29
Toward microbenchmarking XQuery
Information Systems
Let SQL drive the XQuery workhorse (XQuery join graph isolation)
Proceedings of the 13th International Conference on Extending Database Technology
Efficient physical operators for cost-based XPath execution
Proceedings of the 13th International Conference on Extending Database Technology
Optimizing XML twig queries in relational systems
Proceedings of the Fourteenth International Database Engineering & Applications Symposium
Context-preserving XQuery fusion
APLAS'10 Proceedings of the 8th Asian conference on Programming languages and systems
Hash-based structural join algorithms
EDBT'06 Proceedings of the 2006 international conference on Current Trends in Database Technology
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XQuery expressions can manipulate two kinds of order: document order and sequence order. While the user can impose or observe the order of items within a sequence, the results of path expressions must always be returned in document order. Correctness can be obtained by inserting explicit (and expensive) operations to sort and remove duplicates after each XPath step. However, many such operations are redundant. In this paper, we present a systematic approach to remove unnecessary sorting and duplicate elimination operations in path expressions in XQuery 1.0. The technique uses an automaton-based algorithm which we have applied successfully to path expressions within a complete XQuery implementation. Experimental results show that the algorithm detects and eliminates most redundant sorting and duplicate elimination operators and is very effective on common XQuery path expressions.