An Efficient XML Index Structure with Bottom-Up Query Processing

摘要

With the growing importance of XML in data exchange, much research has been done in proving flexible query mechanisms to extract data from structured XML documents. The semi-structured nature of XML data and the requirements on query flexibility pose unique challenges to database indexing methods. Recently, ViST that uses suffix tree and B~+Tree was proposed to reduce the search time of the documents. However, it can cause a lot of unnecessary computation and I/O when processing structural join queries because the numbering scheme of ViST is not optimized. In this paper, we propose a novel index structure to solve the problems of ViST. Our index structure provides the bottom-up query processing method to efficiently process structural queries. Our experiments show that the proposed index structure is efficient in processing both single-path and branching queries with various wild-cards ('~*' and '//').