Accelerating value-based lookup of XML document in XQuery

摘要

A method and apparatus for accelerating value-based lookups of XML documents in XQuery is provided. XML indices can help to optimize SQL queries of XML documents stored in object-relational databases. Certain SQL/XML functions such as XMLTABLE( ) use XQuery expressions to query XML documents. Previously, such queries could not use the XML index because the PATH table of the XML index was not defined for XQuery semantics. Techniques described herein extend the XML index for use with queries that require evaluation of XQuery expressions. Consequently, techniques described herein accelerate value-based lookups of XML documents in XQuery by introducing the possibility of an index-assisted evaluation of XQuery expressions.