利用XML配置文档动态地创建DataSet对象

Create DataSet Object Dynamicly By XML Configuration Document

本文描述了使用 Singleton 工厂类创建表示数据库视图的数据集(DataSet)对象的一种机制。这里视图代表一个特殊用户角色感兴趣的数据,它包含一些表和 SQL 语句的集合。每个视图在基于 XML 的配置文档中表示为一个结点,它的结构用 Schema 来描述,数据存储在 XML 文档中。通过基于 XPath 的查询语句来查找存储在 XML 文档中视图的结点配置信息,工厂类可以依据配置信息创建数据集。由于可以动态地增加结点,工厂类也具有了在运行时动态扩展的能力。

The text describes a way to Create a Dataset object in database view.These views represent the data of a special user.It contains some tables and SQL statement sets.Every view represents a node based XML Configuration Document.Its structure is described by Schema,The data are stored in a XML Configuration Document.To search the node configuration information stored in the XML Configuration Document by using XPath query statement,the factory class can Create a Datasct by its configuration.Because of the dynamically increased node,that factory class is capable of dynamic extending at run time.