In-Depth

.NET Programmers Ally to Save XQuery

XQuery’s tardiness is wearing on some long-time supporters such as Microsoft, which plans to drop XQuery support from its .NET framework

• By Stephen Swoyer
• 05/11/2005

After almost seven years in the making, it appears that XQuery’s tardiness is starting to wear on some long-time supporters—including Microsoft Corp., which earlier this year announced plans to drop support for XQuery in the version 2.0 release (code-named “Whidbey”) of its .NET application framework.

First proposed in 1998, XQuery—which defines a single-query standard for access to both structured and unstructured data—has since been through more than half a dozen W3C working drafts, the first appearing in June 2001. The W3C’s XML Query and eXtensible Stylesheet Language (XSL) working groups are together collaborating on the XQuery draft specifications.

But XQuery itself remains elusive. The final XQuery standard, after all, was supposed to have been approved 30 months ago, then 18 months ago, then—proponents hoped—six months ago. Talk about a long gestation period.

It’s also worth noting that Microsoft hasn’t completely divested itself of its XQuery commitments: SQL Server 2005, when it appears, will feature native support for XQuery, and Microsoft remains a member in good standing of the World Wide Web Consortium’s (W3C) XQuery standards committee.

Microsoft says it’s a question of XQuery’s stubborn incompleteness: a final standard has been pushed back (once again) to 2006, says the software giant, “making it impossible … for us to guarantee forward compatibility between any XQuery support in .NET 2.0 and the eventual XQuery 1.0 recommendation.”

As it turns out, Microsoft’s move hasn’t been accepted with equanimity. A surprising number of users are already working with the XQuery technology, after all. What’s more, several companies have deployed XQuery-based applications in production environments. There’s also a thriving cottage industry of ISVs who offer XQuery-based XML development tools or XQuery-ready applications.

Last week, DataDirect Technologies, a division of Progress Software Corp., which markets data connectivity components and XML development tools, launched an online petition in the hope of “convinc[ing] Microsoft of the overall importance of supporting XQuery in the .NET framework” (see http://www.stylusstudio.com/xquery/xquery_activist_kit.html).

At this point, the company claims to have gathered 140 signatures from members of Microsoft’s Most Valuable Professionals (MVP) program. MVPs carry a lot of weight with Microsoft: Typically culled from among the ranks of prolific (or exceptionally helpful) contributors to Microsoft’s product support newsgroups, MVPs address many user questions and help troubleshoot sophisticated issues that might otherwise ensnare (or go overlooked by) Microsoft product managers or support specialists.

What’s more, DataDirect claims XQuery 1.0 usage is fast going mainstream: in the company’s recent survey of 550 XML developers, for example, more than half (52 percent) of respondents said they were already working with XQuery 1.0 draft specification, while an additional one-third expressed plans to start working with that technology sometime this year.

XQuery will also enjoy support from all of the major RDBMS vendors. Oracle has long provided a separate XQuery implementation for its flagship database, and Microsoft has also provided a similar add-on feature for SQL Server 2000. What’s more, XQuery should go native in the next versions of Microsoft’s, Oracle’s, and IBM’s RDBMSes.

Microsoft has pulled the plug on native XQuery support in the .NET 2.0 framework, but XQuery tools for developers are available from DataDirect, BEA Systems Inc. (which last year acquired XQuery pure-play ISV Enosys Software), and other sources—including the aforementioned RDBMS kingpins.

IBM and Microsoft, for example, developed an XQuery test suite that they turned over to the W3C. The suite can be used to validate whether a given implementation conforms to the XQuery specification. Similarly, on its AlphaWorks Web site, IBM also provides a test version of an XQuery implementation—called XML for Tables (see http://www.alphaworks.ibm.com/tech/xtable)—that lets users query relational databases as if they were XML documents. Elsewhere on the XQuery front, IBM and Oracle have developed a Java API for XQuery, similar to the JDBC API, that lets Java programs query SQL data sources.

Microsoft hasn’t yet commented on the XQuery petition, and DataDirect and other .NET XQuery proponents are cutting it close. Whidbey is due to ship this summer, after all, and it could be two years or more before Microsoft delivers the next version of its .NET framework.

Related Articles:

XQuery Standard Inches Closer to Reality
http://www.esj.com/Business_Intelligence/article.aspx?EditorialsID=6727

XQuery Use Grows Despite Lack of Finalized Standard
http://www.esj.com/Business_Intelligence/article.aspx?EditorialsID=7260

XQuery—Could Finalized Standard Emerge This Year?
http://www.tdwi.org/research/display.asp?id=6608