XmlQueryExpression |
![]() ![]() |
#include <DbXml.hpp>class DbXml::XmlQueryExpression { public: XmlQueryExpression () virtual ~XmlQueryExpression () XmlQueryExpression (const XmlQueryExpression &) XmlQueryExpression & operator= (const XmlQueryExpression &) ... };
An XmlQueryExpression represents a parsed XQuery expression, and is created by a call to XmlManager::prepare. Parsed XQuery expressions are useful because they allow the cost of query parsing and optimization to be amortized over many evaluations. If indices of a container that may be referenced by a parsed XQuery expression are modified (e.g. add/drop an index) the XmlQueryExpression object should be regenerated by the application.
The copy constructor and assignment operator are provided for this class. The class is implemented using a handle-body idiom. When a handle is copied both handles maintain a reference to the same body.
This object is free threaded, and can be safely shared among threads in an application.
![]() ![]() |
Copyright (c) 1996-2009 Oracle. All rights reserved.