XML Extender

XML Extender enables XML used in Business to Business (B2B) applications to be stored in a relational database. XML is a subset of Standard Generalized Markup Language (SGML). It is a much larger subset than HTML and capable of defining its own markup tags. The ability to define custom markup tags enables XML documents to mark up text by content type rather than the way the data is formatted. This enables meaningful storage of data in an open standard format.

Data Sharing Across Applications

Applications that need to share data need a common interface or format to exchange information. One method of information exchange is to use an API. Examples of common database API standards are ODBC, JDBC, and OLE DB. The problem with application interfaces is that applications are always changing. An application interface that is popular now may rarely be used in the future.

Another method of exchanging information between applications is to use a common data format. One common data format is HTML. The problem with HTML is that it combines document data with formatting directives. It is difficult to interpret the meaning of various data elements. A better data format is XML. XML separates document formatting from the data. A Data Type Definition (DTD) describes the document structure so data elements can be easily interpreted.

Managing XML Documents

Managing a large number of XML documents can be difficult. A natural choice would be to store the documents in a database using the LOB data type. However standard SQL is unable to interpret the XML DTD. The XML document data elements cannot be referenced, inserted, or updated in SQL queries.

XML Extender maps XML documents to and from relational databases. This means that XML documents can be broken down into elements and inserted into a relational database, or a new XML document can be generated from existing relational database tables. XML Extender also supports validating, storing, retrieving, and searching XML documents stored inside a DB2 database or on a local file system.