US Patent 7260572 Method of processing query about XML data using APEX

A method of processing a query about an Extensible Markup Language (XML) data. The XML query processing method includes the first step of representing the XML data in the form of an XML graph, the second step of creating and updating an Adaptive Path indEX (APEX) based on frequently used paths extracted from previously processed XML queries and the XML graph, and the third step of processing an XML query using the APEX. The XML query processing is capable of improving the performance of processing the query by extracting frequently used paths from path expressions having been used as queries for XML data and updating the APEX through the use of the frequently used paths.