Are you a busy SQL Server professional who hasn't learned XML because you don't need it to fulfill your day-to-day job responsibilities? If so, you might want to rethink your reasons for not learning XML.

SQL Server's support for XML continues to grow richer and deeper. If you regularly work with SQL Server, you'll eventually need to know XML. SQL Server 2000, which shipped more than a year ago, includes basic support for handling XML data. However, to stay current with evolving standards and to add new functionality, Microsoft initiated the XML for SQL Server program of feature packs. Microsoft, which makes these fully supported feature packs available as Web downloads, considers the feature packs part of the production version of SQL Server 2000. Unlike service packs, the feature packs include functionality that doesn't ship in the box with SQL Server 2000. XML for SQL Server Web Release 1 (WR1) has been out since early this year, and the recent release of WR2 adds some eagerly awaited XML functionality.

WR2 adds support for XML Schema Definition (XSD) language mapping schemas, client-side XML functionality, a new SQLXML OLE DB provider, a tool that converts XML Data Reduced (XDR) mapping schemas to XSD, and significant performance improvements. SQL Server 2000 users can take advantage of client-side XML functionality to move XML processing to the middle tier for better scalability or to wrap SQL Server stored procedures with T-SQL's FOR XML clause.

Although WR2 is a fully supported feature pack, you should be aware of one support issue. WR2 introduces a set of SQLXML managed classes that let Microsoft .NET developers access SQL Server's XML functionality. These new managed classes require you to install the .NET Framework before you start the installation of XML for SQL Server. However, the .NET Framework is still beta code, whereas WR2 is production-quality software. The WR2 install will run correctly without the beta-level .NET Framework, but if you don't install the .NET Framework, you won't have access to the .NET managed classes. On a similar note, WR2 requires MSXML 4.0, the Microsoft XML parser that's included with the XML for SQL Server download. Microsoft recently released MSXML 4.0 to manufacturing, so your release of SQL Server probably doesn't include this version of MSXML.

Think long and hard before installing beta software such as the .NET Framework on a production SQL Server machine. Treat the XML for SQL Server and MSXML installations as you would any change to your production databases' OS—and make sure you have a back-out strategy.

WR2 is available for download from Microsoft's Web site, which also contains a nice overview of the XML for SQL Server resources.