Saturday, March 22, 2008

XForms, Dyslexia and the Right Brain

Those of you that have worked with me know that I am a little bit of an odd-duck. I have dyslexia. If you ever see me attempt to write on a whiteboard my spelling is at the ninth grade level. My left brain, used for phoneme recognition, never really developed like the rest of you. My right brain had to be co-opted to help out. But one of the skills I seemed to have picked up due to my over-exercised right brain is the ability to visualize multiple complex application architectures and quickly understand architectural tradeoffs. I am one of the few people that seem to be interested in discussing how XForms, metadata registries, ontologies, the semantic web, OWL, RDF, graphs, business rules, BPM and Kimball conformed dimensions all can work together to deliver elegant and cost-effective enterprise-scale solutions. It seems easy for me to simultaneously visualize two or more architectures and it constantly challenges my patience when I have to explain over and over why architecture alternatives will not meet a business requirement.

It turns out that many people that have dyslexia also have the gift of being able to visualize complex systems. Albert Einstein, Thomas Edison, Jackie Steward and Charles Schwab are good examples of dyslexic people that have used the strengths of the right brain to do things that left-brain thinkers could not.

As a right-brain centric person I need to also tell you that I really love the XForms architecture. The magic of a declarative language, MVC, bindings and a dependency graph makes XForms development 10 years more advanced than anything else I have worked with. I think it is beautiful and elegant. It is everything that AJAX and JavaScript application are not. Clean, simple and easy to visualize (for me at least). When someone asks me if I can create an XForms application to do something, I create a mental image in my mind of the model, the view and how events will update instance data in the model using inserts or external submission results. I can easily visualize the bindings of view controls to data elements in the model. Once I can visualize the application clearly, writing the application is just a matter of typing in the code.

I think that my right-brain is also a reason I detest JavaScript and AJAX. It is far too much code to read and trying to visualize how 300 lines of JavaScript enables me to do a drag-and-drop. I want to just add an attribute to an element like "drag-source" and "drop-target" and I want it to just work.

What triggered this posting is that I have been reading Proust and the Squid by Maryanne Wolf. This is a book about how the brain's circuits are used in the reading process. She has a wonderful explanation of how the dyslexic brain co-opts the right brain for reading and enhances it functionality. I didn't really understand the relationship between my defects and my gifts .

So how about you and your development team? Do you have a dyslexic right-brained person on your team? Can they quickly visualize architectural tradeoffs? Have they tried XForms? And if they do, will you be willing to tolerate their disgust of AJAX and JavaScript after they have built their first XForms applications?

For more information about dyslexia check out these two Wikipedia entries:

Friday, March 21, 2008

Great Example of Multi-dimensional Bubble Chart

Here is a beautiful example of a bubble chart display using global population statistics. The example on carbon emissions are very interesting. Note the dimensions
  1. Population of County (size of bubble)
  2. Continent (color of bubble)
  3. Live Expectancy (vertical axis)
  4. Income (horizontal)
  5. Time (the play button)
It is interesting to see the huge impact AIDS has had on the life expectancy in African counties. Imagine if you could see your organizations product sales using this type of graph. This application was done with a software system called Trendalyzer. It was initially developed by Hans Rosling's Gapminder Foundation in Sweden and acquired by Google Inc. in March 2007. This version is a Flash application. Does anyone know of any open-source software that could do this?

Metadata Repositories vs. Metadata Registries

For several years people have been using the terms metadata Registry and Repository inconstantly, imprecisely and almost interchangeably and I would like to weigh in as to how these terms could be used more precisely to allow organizations to effectively to manage metadata processes.

First lets take the definition of a Repository. Webster defines a repository as …a place, room, or container where something is deposited or stored.. Note that here is nothing in this definition about the quality of the things being stored or the process to check to see if new incoming items are duplicates of things already in the repository. If I have 100 users they could each define "Customer" as the see fit and put their own definition into the metadata repository as their own definition. No problems.

On the other had lets take the word Registry. A Registry has the connotation of more than just a shared dumping ground. Registries have the additional capability to create workflow processes to check that new metadata is not a duplicate (for a given namespace). One of the definitions from Webster is an official record book. Note the word official.

A Repository is similar to a front-porch of a house. No locks prevent new things from landing there. But a Registry is a protected back room where human-centric workflow processes are used ensure that metadata items are non-duplicates, precise, consistent, concise, distinct, approved and unencumbered with business rules that prevent reuse across an enterprise. These registries have become the central foundation that agility can be baked-in to many enterprise process. The latest version of the Kimball's Data Warehouse Lifecycle Toolkit (which is actually a very good read) even goes as far as to call their process "metadata-driven". Not different the model-driven development world.

Registries have the implicit connotation of trust behind them. They now serve a a central process for the creation of shared meaning across the enterprise. Definitions in a registry have been vetted by an enterprise-level organization that has the responsibility of enterprise data stewardship. They have a high probability of being consistent with industry best-practices and vertical industry standards. Registries are the go-to source for creating canonical XML schemas, enterprise ontologies or conformed dimensions in a OLAP cube. Repositories are personal or small departmental definitions of an isolated view of the world.

None of these ideas are really new. They are at the core of the ISO/IEC 11179 metadata registry standard. Note that they don't call it a repository standard! People are just now starting to understand how important Registries are in most enterprise-wide systems. The growth of Business Intelligence and Enterprise Data Warehouse terminology and Service Oriented Architectures is a good place to see the rise of repositories and registries. We now see service registries, portlet registries, model registries...the list goes on-and-on.

Much of the background on the differences between the use of repositories and registries can be traced way back to the early days of object-oriented systems in the 1995 book Succeeding with Objects by Adele Goldberg and Kenneth Rubin. This was one of the first books on enterprise reuse strategies and they defined the concept enterprise asset reuse and the need for a trust-driven repository as a basis for reusing assets. They identified a multi-step process for reviewing new submissions to determine if the submission duplicated existing assets. They showed how critical it was to classify items in a registry and search an existing registry for duplicates before new items are added. If you can get a copy of the book I would suggest you read the section on "Set Up a Process for Maintaining Reusable Assets" on page 245.

The book then goes on to show how organizations can and should be structured to reuse these assets and gives the pros and cons of the differing organization structures and their impact on reuse. This is the basis for the data governance and data stewardship movement in many organizations today.

So the next time someone uses the word registry or repository in a conversation, ask them if they are using the definition of the word that is consistent with the corporate business term registry or is their own private definition from their own repository of imprecisely used buzzwords.

Sunday, March 09, 2008

XForms Tutorial and Cookbook Voted Featured Wikibook!

I am happy to announce that the XForms Tutorial and Cookbook that I have been working on for over a year been voted a "Featured Book" on the wikibooks web site. A quote from the award:

XForms is a featured book on Wikibooks because it contains substantial content, it is well-formatted, and the Wikibooks community has decided to feature it on the main page or in other places. Please continue to improve it and thanks for the great work so far!

Here are some stats on the book so far: 90 sample programs
116 chapters
626 edits
28,811 words
29 registered authors

One of the big tasks is to start to move some of the advanced XForms examples that require siginficant server-side logic to a seperate server-specific book. As a pilot I have started an XRX cookbook for people using REST interfaces and the eXist server.

I would like to thank the over 30 others that have contributed ideas and content to this wikibook. We still have lots of work to do to cleanup the example programs, make them more consistent and add additional examples for new XForms students. But I believe it is one of the best examples of collaborative training that I have worked on in the last few years.