Thursday, January 31, 2008

QlikView Scripts Are Powerful, Not Sexy

I spent some time recently delving into QlikView’s automation functions, which allow users to write macros to control various activities. These are an important and powerful part of QlikView, since they let it function as a real business application rather than a passive reporting system. But what the experience really did was clarify why QlikView is so much easier to use than traditional software.

Specifically, it highlighted the difference between QlikView’s own scripting language and the VBScript used to write QlikView macros.

I was going to label QlikView scripting as a “procedural” language and contrast it with VBScript as an “object-oriented” language, but a quick bit of Wikipedia research suggests those may not be quite the right labels. Still, whatever the nomenclature, the difference is clear when you look at the simple task of assigning a value to a variable. With QlikView scripts, I use a statement like:

Set Variable1 = ‘123’;

With VBScript using the QlikView API, I need something like:

set v = ActiveDocument.GetVariable("Variable1")
v.SetContent "123",true

That the first option is considerably easier may not be an especially brilliant insight. But the implications are significant, because they mean vastly less training is needed to write QlikView scripts than to write similar programs in a language like VBScript, let alone Visual Basic itself. This in turn means that vastly less technical people can do useful things in QlikView than with other tools. And that gets back to the core advantage I’ve associated with QlikView previously: that it lets non-IT people like business analysts do things that normally require IT assistance. The benefit isn’t simply that the business analysts are happier or that IT gets a reduced workload. It's that the entire development cycle is accelerated because analysts can develop and refine applications for themselves. Otherwise, they'd be writing specifications, handing these to IT, waiting for IT to produce something, reviewing the results, and then repeating the cycle to make changes. This is why we can realistically say that QlikView cuts development time to hours or days instead of weeks or months.

Of course, any end-user tool cuts the development cycle. Excel reduces development time in exactly the same way. The difference lies in the power of QlikView scripts. They can do very complicated things, giving users the ability to create truly powerful systems. These capabilities include all kinds of file manipulation—loading data, manipulating it, splitting or merging files, comparing individual records, and saving the results.

The reason it’s taken me so long time to recognize that this is important is that database management is not built into today's standard programming languages. We’re simply become so used to the division between SQL queries and programs that the distinction feels normal. But reflecting on QlikView script brought me back to the old days of FoxPro and dBase database languages, which did combine database management with procedural coding. They were tremendously useful tools. Indeed, I still use FoxPro for certain tasks. (And not that crazy new-fangled Visual FoxPro, either. It’s especially good after a brisk ride on the motor-way in my Model T. You got a problem with that, sonny?)

Come to think of it FoxPro and dBase played a similar role in their day to what QlikView offers now: bringing hugely expanded data management power to the desktops of lightly trained users. Their fate was essentially to be overwhelmed by Microsoft Access and SQL Server, which made reasonably priced SQL databases available to end-users and data centers. Although I don’t think QlikView is threatened from that direction, the analogy is worth considering.

Back to my main point, which is that QlikView scripts are both powerful and easy to use. I think they’re an underreported part of the QlikView story, which tends to be dominated by the sexy technology of the in-memory database and the pretty graphics of QlikView reports. Compared with those, scripting seems pedestrian and probably a bit scary to the non-IT users whom I consider QlikView’s core market. I know I myself was put off when I first realized how dependent QlikView was on scripts, because I thought it meant only serious technicians could take advantage of the system. Now that I see how much easier the scripts are than today’s standard programming languages, I consider them a major QlikView advantage.

(Standard disclaimer: although my firm is a reseller for QlikView, opinions expressed in this blog are my own.)

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