Both PHP and Oracle provide comprehensive support for XML and XML-related technologies. Practically, this means you can perform any XML processing either with PHP or inside an Oracle database. While PHP allows you to construct and transform XML by using either PHP's XML extensions or PEAR XML packages, Oracle provides the Oracle XML DB, which has a wide set of XML features that can be used to efficiently store, retrieve, update, as well as transform XML data and generate it from relational data.
This chapter explains how to effectively use XML techniques and technologies available in PHP and Oracle when building XML-enabled PHP/Oracle applications.
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