Skipping Strategies for Efficient Structural Joins

The structural join is considered a core operation in processing and optimizing XML queries. Various techniques have been proposed for efficiently finding structural relationships between a list of potential ancestors and a list of potential descendants. This paper presents a novel algorithm for efficiently processing structural joins. Moreover, previous work which performs well usually relies on external index structures such as a B-tree, which increases both the storage and memory overheads. Our proposal in this paper does not require any such data structures, and hence can be easily implemented and incorporated in any existing system. Experiments show that our method significantly outperforms previous algorithms.