Optimizing xslt based on input xml document structure description and translating xslt into equivalent xquery expressions

Abstract

Transformation of a set of XML documents via an XSLT stylesheet is made more efficient by rewriting the stylesheet at compile-time, based on the structural description of the set of XML documents, into an optimized stylesheet containing fewer dynamic template-matching calls than the original stylesheet. This rewritten stylesheet can be further rewritten into a set of XQuery expressions. At compile-time, the particular transformation templates that are appropriate for transforming the particular nodes contained in the set of XML documents are determined, and XSLT calls to the templates are converted to calls to corresponding XQuery user-defined functions. Determination of the appropriate transformation templates may be based on the structural description of the input set of XML documents, such as an XML Schema or Document Type Definition. The data from each template is translated into corresponding XQuery constructors, instructions from the template are translated into XQuery expressions, and the XQuery functions are inlined if possible.