Title
Kappa-join: efficient execution of existential quantification in XML query languages
Abstract
XML query languages feature powerful primitives for formulating queries, involving comparison expressions which are existentially quantified. If such comparisons involve several scopes, they are correlated and, thus, become difficult to evaluate efficiently. In this paper, we develop a new ternary operator, called Kappa-Join, for efficiently evaluating queries with existential quantification. In XML queries, a correlation predicate can occur conjunctively and disjunctively. Our decorrelation approach not only improves performance in the conjunctive case, but also allows decorrelation of the disjunctive case. The latter is not possible with any known technique. In an experimental evaluation, we compare the query execution times of the Kappa-Join with existing XPath evaluation techniques to demonstrate the effectiveness of our new operator.
Year
DOI
Venue
2006
10.1007/11841920_1
Xsym
Keywords
Field
DocType
conjunctive case,xml query language,xml query,experimental evaluation,new operator,xpath evaluation technique,efficient execution,disjunctive case,new ternary operator,decorrelation approach,existential quantification,query execution time,query language
Query language,Decorrelation,Programming language,Expression (mathematics),XML,Existential quantification,Computer science,Theoretical computer science,XPath,Operator (computer programming),Predicate (grammar),Database
Conference
Volume
ISSN
ISBN
4156
0302-9743
3-540-38877-X
Citations 
PageRank 
References 
1
0.36
19
Authors
4
Name
Order
Citations
PageRank
Matthias Brantner120714.33
Sven Helmer253769.96
Carl-christian Kanne364453.20
Guido Moerkotte42136649.11