Using a simplified shopping cart XML example, the content shows how to safely modify an XML element while properly handling namespaces and following the required copy / modify / return pattern defined by the XQuery standard.

The example intentionally reflects real-world constraints, where the XML is already stored as CLOB and changing the data model to XMLTYPE is not an option. The focus is on clarity, maintainability, and correct usage of supported Oracle XML features rather than deprecated functions.