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DBMS_XMLPARSER

Using DBMS_XMLPARSER, you can access the contents and structure of XML documents.

This chapter details the following:

Functions and Procedures of DBMS_XMLPARSER

Description of DBMS_XMLPARSER

The Extensible Markup Language (XML) describes a class of data objects called XML documents. It partially describes the behavior of computer programs which process them. XML is an application profile or restricted form of the Standard Generalized Markup Language (SGML). By construction, XML documents are conforming SGML documents.

XML documents are made up of storage units called entities, which contain either parsed or unparsed data. Parsed data is made up of characters, some of which form character data, and some of which form markup. Markup encodes a description of the document's storage layout and logical structure. XML provides a mechanism to impose constraints on the storage layout and logical structure.

A software module called an XML processor is used to read XML documents and provide access to their content and structure. It is assumed that an XML processor is doing its work on behalf of another module, called the application. This PL/SQL implementation of the XML processor (or parser) followed the W3C XML specification (rev. REC-xml-19980210) and included the required behavior of an XML processor in terms of how it must read XML data and the information it must provide to the application.

The following is the default behavior for this PL/SQL XML parser:

• A parse tree which can be accessed by DOM APIs is built
• The parser is validating if a DTD is found, otherwise, it is non-validating
• Errors are not recorded unless an error log is specified; however, an application error will be raised if parsing fails