I’ve driven through and around Manhattan before, but I’ve never really been in the city. I had a scant 20 hours to enjoy the place, which I did with some abandon. I’m fundamentally a man of the suburbs, but I love the city, and lovers of the city are truly bound to enjoy Midtown. I will certainly be back at my earliest opportunity.

The JUG—or rather, the SIG—is led by the redoubtable Frank Greco, CEO of Crossroads Technologies (no relation). I gave my talk on Gaelyk, shown here:

There was lively discussion about Gaelyk’s very lightweight structure as a framework, and the limitations imposed by that structure. Many of the SIG attendees are Enterprise developers in the classical sense, so a product like this was understandably strange to them. And to be sure, I would never commend it for use in anything of even moderate complexity. However, for sites so simple you don’t want to incur the cognitive cost of dealing with a larger framework, and for which any kind of sophisticated hosting would be overkill, Gaelyk is a perfect fit. Interaction with the audience moved delightfully to a discussion of the way our tools shape the way we solve problems, and even the kinds of problems we consider tractable. Winston Churchill was quoted. Neal Postman was referenced. Nick Carr’s latest book was commended. Win, win, and win.

All in all, an enjoyable trip and a solid talk with a first-class JUG. Thanks to Jay Zimmerman and the NYC Java SIG for the experience.

I had two main examples to show. The first was a simple (and contrived) transformation of an OPML file into an Excel spreadsheet and a text file. The Excel file contained a list of the names and URLs of all my feeds in a human-readable format. The text file was supposed to contain a list of the unique link types (hint: they were all “rss”), but that part of the demo actually didn’t work properly due to some fault of mine. This being an occupational hazard in live coding not to be dwelt upon when your audience is patiently waiting, I dropped it and moved on.

After the first demo, I talked about basic data warehousing principles a little bit as outlined in The Data Warehouse ETL Toolkit by Kimball and Caserta. This kind of thing is tricky with a diverse audience, because the speaker runs the dual risks of insulting the informed and not informing those new to the subject. Brevity is usually the best policy.

The second demo showed a real-life transactional schema from a start-up I had been involved with a few years back. (The present custodians of the data were kind enough to share a sanitized copy of it with me for this demo.) I showed a few transformations of transactional data of varying levels of complexity into the relevant fact and dimension tables, including some look-ups from external text files and one or two interesting joins on the transactional inputs. Mind you, I didn’t proceed to show any neat analytical tools running on the newly minted warehouse, but the OLAP world is your oyster once the ETL job runs to completion. Relatively speaking.

A Talend job showing the creation of an order line item dimension.

I was frank about Talend’s weaknesses. There are a few tutorial screencasts on the web site, but other than that I don’t consider the getting-started documentation to be particularly smooth. The Business Modeler is a confusing addition to the product—a third-rate drawing program that distracts the newcomer and adds no discernable value to the suite. The lack of credible Mac support is as disappointing as it is surprising, given that the tool is entierly Eclipse-based. However, I still see the tool as an option very much worth evaluating if you have needs in the space.

All in all, I’m happy with how the talk went, and I’d like to put the tool to use in a production environment at some point soon. I hope to be able to make a few upgrades to the talk and give it at some other local groups as the opportunity arises. I’ll update with a link to Slideshare as soon as I get the deck upgraded.

Another thing: as threatened on Twitter, I did wear all black to the talk. And yes, Matthew McCullough did play a Johnny Cash song just before the meeting got started. See his post on the event for another account of how it went.