Research Of Holistic XML Tree Pattern Matching For XQuery Language

With the popularization and development of the Internet, XML is widely used in heterogeneous platforms and data exchange/share for heterogeneous information In order to standardized XML query and processing, the World Wide Web Consortium (W3C) developed XQuery, and released it as a standard query language for XML data With the consideration of the semi-structured characteristic of XML data and the functional language feature of XQuery, high-performance XML query processing and XQuery language implementation technology gained widespread attention, and became a popular research topic of database technology in recent yearsBeing semi-structured, XML data is different from relational data Most parts of queries expressed in standard XML query language focus on structural feature of XML data Twig query can form pattern tree according to the tree structural feature in XML queries, and process it effectively using pattern-matching algorithms Among the many XML query processing techniques, holistic matching approach such as TwigList has become one of the core technologies in high-performance XQuery implementation technology because it fully employed the tree structural feature of XML dataThis paper analyzed the development and problems of holistic Twig matching algorithms, resolved various issues after introducing Twig matching into XQuery engine First of all, we proposed a novel way to handle both the out-of-orderness issue and optimization of parent-child relationship by improving TwigList, named TwigLinkedList Subsequently, we represented an enumeration method and an approach dealing with predicate after introducing Twig query These made it effective for Twig query module to be integrated into XQuery engineOur algorithm was tested against TwigList in terms of the query processing time and memory usage Experimental results showed that, TwigLinkedList algorithm can reduce the redundant intermediate results, thereby enhance the Twig query efficiency, and support for high-performance implementation of the XQuery language...