Counting Relaxed Twig Matches in a Tree

Abstract. We consider the problem of accurately estimating the number of approximate XML answers for a given query, and propose an efficient method that (1) accurately computes selectivity estimates for each relaxed XML query, using a natural generalization of the correlated subpath tree (CST) summary structure, and (2) carefully combines these estimates by analyzing the nature of overlap between the different relaxed twig queries.

• Type: Conference
• Year: 2004
• Where: DASFAA
• Authors: Dongwon Lee, Divesh Srivastava
• Keywords: Approximate Xml Answers, Correlated Subpath Tree, DASFAA 2004, Database, Relaxed Twig Queries