Oracle Essentials: Oracle9i, Oracle8i and Oracle8, Second Edition

XML

XML, as we mentioned earlier, is a standard that has gained a lot of attention through its connection with the Internet and the backing of many important software companies, most prominently Microsoft.

Oracle includes a number of features that support XML, such as its XDK (or XML development kit) for Java, C, C++, and PL/SQL. The XDK lets developers send, receive, and interpret XML data from applications written in their respective languages. In Oracle9i, the XDK also supports the XML schema standard for defining the datatypes for a particular XML document, which replaces the old method of using Document Type Definitions (DTDs). The Oracle9i version of the XDK also includes two JavaBeans (or components), the DBAccess Bean and the DBView Bean, that make it easier for developers to define access to and view XML data stored in the database.

Oracle9i also provides these XML-related features:

XML class generators for Java and C++

Create classes from XML schema definitions

XML SQL utility

Supports reading and writing XML data to and from the database using SQL. You can also get most of this functionality by using the DBMS_XMLGEN built-in package.

XSQL servlet

Generates XML documents from one or more SQL queries and uses XSL stylesheets to format the results. This servlet can also be used to insert, update, and delete data using XML.

Finally, the Oracle9i release includes the new XMLType datatype, which we described in Chapter 4. This datatype allows native storage of XML documents ...