The Application Of Xpath And XSLT In Querying XML Document

The opinions and facts that this composition is based on are as follows: XML is only a kind of the expression methods of typed value. Software agency program can interchange and interoperate data by this expression method. In this opinion, the grammer of XML is ranked among the minor details. Xpath specifications of XML maintain the hierarchy and structure of source document, apply to access the independent node of XML document . XSLT specifications apply to process the results of query. We may operate and restructure source document optionally and easily by XSLT and Xpath. This article begins with the background of the appearance about XML, The author summaries the defects of HTML and the advantages of XML, then analyses the structure of XML document. XML Infoset provides a group of consistent definitions for these specifications that need to quote the information about XML document, hence we introduce XML Infoset at first. Among this paragraph, seven kinds of XML Infoset items are introduced in detail, which are relevant to seven kinds of node types about Xpath data model. Xpath is explicated in detail in the second section, from concising Xpath and explicating Xpath data model to introducing Xpath expression. In this section, Xpath location path expression is explained entirely and finely. In the end, Xpath core functions are elaborated. XSLT is introduced in the third section. The narrative in this section is based on the opinion that XSLT may be thought of as programming language, and that XSLT engine can process XSLT document like processing a program. XSLT programming model includes exemplar-based model, procedural model and declarative model. The content of this composition contains procedural model and declarative model. In the section, at first, XSLT is introduced concisely, then XSLT structure and processing mechanism are analysed, Xpath application to XSLT is also talked about, secondly, these functions and elements that are defined in XSLT are elaborated entirely and finely, finally, the most important component in XSLT, namely template, is introduced, including built-in template rules and conflict resolution for template rules. In the fourth section, many facets applying Xpath and XSLT to querying XML document are narrated, including processing query model, managing documents, modular components, as well as the function of template in the course of querying XML document, such as repetition, conditional processing, sorting, grouping and other questions about math. In the second fragment of this section, several examples applying Xpath and XSLT to querying XML document are provided. In the third fragment, XQuery1.0 is introduced concisely.In the final section of this article, the application of Xpath and XSLT in querying XML data which is stored by RDBMS is explored., then comparing XSLT1.0 with XQuery1.0 is the conclusion of the composition.