XQuery For Web Services

XQuery's incompleteness isn't stopping vendors like Oracle and IBM from including it in forthcoming versions of their enterprise-class database software.
Sandeepan Banerjee, director of product management for XML at Oracle, said Oracle will have a full implementation with release 2 of Oracle 10g Database, slated for late summer.
While the engineer believes there is a place for XQuery, he doesn't think it will replace traditional languages like SQL, at least not in the next few years.

"We take XQuery seriously," Banerjee said in an interview. "We see it as having the potential for becoming an important query language. I don't think XQuery will be the only query language in the next one to two years because we see highly structured data still being searched by SQL. We also see unstructured data being searched by Google search engines."
Rather, the engineer said XQuery will have a market niche that is somewhere in the middle, where the data is all XML or has some structure to it. "Enough to query on, but not so much structure that you're better off putting it in a relational database and doing SQL on it," he said.

Paul Rivot, director of competitive technology for IBM, agreed with Banerjee for the most part, noting that IBM will have full XQuery support in the follow-up to its Stinger DB2 Universal Database release.
That update isn't likely to beat Oracle's 10g release 2, but it will appear before 2006. Until then it'll bake in preparation for the next DB2 beta.

Rivot said one of the challenges his company faces is querying relational data and XML at the same time and making them transparent, so that people that know SQL can leverage XQuery and use its capabilities to integrate both languages.
"We see a lot of promise in using XML and XQuery to move data back and forth, and we think it will be particularly useful for Web services (define)," Rivot said in a recent interview.

This makes sense because most Web services are written in XML, making XQuery a natural back-end support mechanism for broad application-to-application communication. But the matter depends on the context, Banerjee said.
"Web services search is going to be used widely," Banerjee said. "To some extent whether XQuery is used as a query syntax for Web services depends on what the services do. Keyword searches don't need it. If they do complex things like purchase-order invoices, there is more space for XQuery to be a Web services query syntax."

Forrester Research analyst Noel Yuhanna said he sees XQuery as something that will be used to tie together newer applications that require greater interaction or integration with data repositories. The idea that XQuery is becoming a standard is exciting to people who want to develop more XML-based software for grid computing and Web services, he said.
"These are customers who want to put an effort in XML because it provides better data sharing, which is essential when dealing with real-time information," Yuhanna said. "XML has had a slow start but we're certainly seeing it as more appealing with new applications."

For the near term, both Banerjee and Rivot thought Kim's outlook may be a tad optimistic, considering that it was culled from XML fans. But they agreed that XQuery has more promise now than ever despite the fact that herds of specs are months away from becoming standards.
In fact, Banerjee went so far as to predict a convergence of SQL, XQuery and keyword queries of unstructured Google in five or more years. That will be just fine for Kim, who said he believes strongly in the broad applicability of XQuery.