A database that stores XML documents. There are two types. The first is the "XML-enabled database," which is a relational or object-oriented database that has been extended to hold XML data. In this method, there is always a conversion to and from the XML document to the underlying structure such as rows and columns in the relational model. In addition, the XML-enabled database may only store part of the XML document. The second is the "native XML database," which indexes XML documents directly and stores the entire XML document and related elements. Depending on the application, the native XML database may provide better performance than the XML-enabled database. For more information on XML databases, visit Ron Bourret's site at www.rpbourret.com. See round tripping.