In this case, you'll probably need a relational database and software to transfer the data between XML documents and the database.If your applications are object-oriented, you might even want a system that can store those objects in the database or serialize them as XML.However, it was always somewhat unrealistic, as many XML documents are not strictly data-centric or document-centric, but somewhere in between.So while the data-centric/document-centric divide is a convenient starting point, it is better to understand the differences between XML-enabled databases and native XML databases and to choose the appropriate database based on your processing needs." An XML document is a database only in the strictest sense of the term. In many ways, this makes it no different from any other file -- after all, all files contain data of some sort. For example, it is self-describing (the markup describes the structure and type names of the data, although not the semantics), it is portable (Unicode), and it can describe data in tree or graph structures. For example, it is verbose and access to the data is slow due to parsing and text conversion.
At the time this paper was originally written (1999), it was a convenient metaphor for introducing native XML databases, which were then not widely understood, even in the database community.
This is usually a matter of intent, but it is important because all data-centric documents share a number of characteristics, as do all document-centric documents, and these influence how XML is stored in the database.
The next two sections examine these characteristics.
The first question you need to ask yourself when you start thinking about XML and databases is why you want to use a database in the first place. Are you looking for a place to store your Web pages?
Is the database used by an e-commerce application in which XML is used as a data transport?