Grouping and optimization of XPath expressions in DB2 ® pureXML
Andrey Balmin, Fatma Özcan, Ashutosh Singh, Edison Ting · 2008
Several XML DBMSs support XQuery and/or SQL/XML languages, which are based on navigational primitives in the form of XPath expressions. Typically, these systems either model each XPath step as a separate query plan operator, or employ holistic approaches that can evaluate multiple steps of a single XPath expression. There have also been proposals to execute as many XPath expressions as possible within a single FLWOR block simultaneously in a data streaming context.