Two weeks ago several of my colleagues and I were lucky enough to take a course on “XQuery for Documents” taught by Michael Sperberg-McQueen.

I’ve taken courses on XQuery before—all excellent—but this one was absolutely unique.

While Michael wasn’t directly involved in the working group that produced the XQuery language, he wasn’t far from it—given his involvement with the W3C and the creation of XML and XSD, not to mention the creation of TEI.  Thus, besides just giving an expert introduction to XQuery, he also shed light on the communities who came together, with different interests, personalities, politics, and intellectual frameworks, to create this remarkable language.

My colleagues and I—all historians, some who specialize in the history of technology—were fascinated by this aspect of the course.  We came away with a solid foundation in the language, and an appreciation for the milestone it marks in the history of programming languages and technology.

(The creation of XQuery, as well as the creation of TEI, would be two worthy dissertation topics.)

Inspired by Michael’s course, I’ve begun thinking about ways to both share my own appreciation for XQuery and related technologies, tools, and tips that I have discovered in my own work, and to give this a human dimension, rather than just a purely instructional one.  I’ve heard it said that the best camera is the one that you have with you.  In that spirit, I’ll start writing here, in a blog that I already have.

So, let’s begin with a brief introduction about how I came to learn XQuery.

In mid-2007, as a freshly minted history PhD, my new job presented me with the challenge of revamping a website for a group of venerable historical publications.  (I’ve written an article about the project.) After researching the formats in use for encoding books and historical documents, I decided to adopt TEI as the format for the publications.   TEI P5—the standard’s 5th major version—was released in October 2007, just in time for my project to adopt it and benefit from its many advances from the start.

This left the question: how to turn the huge volumes of TEI into a website that allow historians and the public to view, browse, and search the publications?  In a superb stroke of luck, I met James Cummings at the TEI conference at U Maryland College Park in October 2007 and told him about my project.  James encouraged me to look into native XML databases.

James’ suggestion led me to eXist-db.  eXist-db’s Shakespeare demos impressed me with their speed and precision.  Moreover, it supported XSLT, which would allow me to use the stylesheets I had adapted from TEI community for turning my XML into HTML for the web.

But besides XSLT, eXist-db also used XQuery for its search and scripting operations.  XQuery 1.0 had just achieved recommendation status in January 2007, and Priscilla Walmsley’s O’Reilly book on XQuery was published in June—the month I graduated.

As I taught myself XQuery with eXist-db (not to mention the indispensable oXygen XML Editor), I found myself ever more comfortable with XQuery.  Thanks to an invaluable hint in the right direction by David Sewell (using the same typeswitch-based approach he outlined in this mailing list posting of his), I migrated all of my XSLT routines to XQuery.  Now, rather than having to master two languages, I could focus on the one that did everything I needed: XQuery.

Ever since that moment, I’ve used XQuery almost exclusively, and together with TEI, eXist-db, and oXygen, it has been my gateway into the world of digital humanities and software development.  XQuery was challenging to learn but still very accessible.  The successes have been rewarding.  Even after five years I am still learning new aspects of the language and uncovering new ways to apply it.

After several years of being the sole user of XQuery in my office, I’m thrilled that so many of my colleagues are learning XQuery.  It makes perfect sense given the amount of TEI and XML that we now have created.  Thanks to Michael for getting us started, and linking us intellectually to the shared sense of purpose and possibilities that led to the creation of XML, TEI, XQuery and the other foundational standards that have enabled and empowered us to do our work.

I look forward to writing more (probably here, but if elsewhere, I’ll post a link)—for them, and anyone interested in following along.