Towards Cost-based Optimizations of Twig Content-based Queries

Abstract In recent years, many approaches to indexing XML data have appeared. These approaches attempt to process XML queries efficiently and sufficient query plans are built for this purpose. Some effort has been expended in the optimization of XML query processing [20]. There are not many works that take cost-based query optimizations into account. In work [20], we find some cost-based considerations, however, they work only with one type of structural join and one type of underlying index. There are works depicted two types of query processing as well [10, 17]. The first type applies an element-based index, the second type applies a navigation in a persistent DOM-like structure. In our work, we propose usage of two path-based indices that provide significant potential for a query optimization based on a cost-based join selection. We can identify some classes of approaches for efficient processing of XML queries. The first class includes approaches based on shredding [18] (storing an...

• Type: Conference
• Year: 2008
• Where: DATESO
• Authors: Michal Krátký, Radim Baca
• Keywords: Database, DATESO 2008, Join Algorithm, Structural Join, XML Queries