ReadWriteWeb has an article on non-traditional databases. It does a good job of explaining the good and the bad aspects of developing to a key/value database.

Among the bad is the lack of integrity support in key/value databases. I am not convinced this is a huge issue. I have seen production relational databases that do not have integrity constraints.

Data that violate integrity constraints cannot physically be entered into the database. These constraints don’t exist in a key/value database, so the responsibility for ensuring data integrity falls entirely to the application.

Legacy database systems require a data modeling process. Actually I see this as a downside. Typically as a project matures, the data model changes often. This requires changes to both the model and the supporting code. Key/value databases move the responsibility to the application and eliminate the time it takes for the modeler to update the model, change the database schema and communicate these changes.

One of the other key benefits of a relational database is that it forces you to go through a data modeling process. If done well, this modeling process create in the database a logical structure that reflects the data it is to contain, rather than reflecting the structure of the application.

Lastly, the author points out the multi-tenant limitations Google and Amazon put in place to prevent one user from overloading a non-traditional database in a shared environment.

Key/value databases are usually multi-tenanted, which means that a lot of users and applications will use the same system. To prevent any one process from overloading the shared environment, most cloud data stores strictly limit the total impact that any single query can cause. For example, with [Amazon’s] SimpleDB, you can’t run a query that takes longer than 5 seconds. With Google’s AppEngine Datastore, you can’t retrieve more than 1000 items for any given query.

What do you think, friends?

photo credit: -Renegade-

And now some stuff that has been on my mind.

• What the Netflix Prize 2 gonna be like?
• Why can’t I get motivated to participate in this year’s NaNoWriMo?
• Can I do anything cool with Raphaël?
• When is my copy of Call of Duty: Modern Warfare 2 with the night vision goggles going to arrive?
• Why are the retailers already selling Christmas junk?
• Why does the Lord of the Rings Trilogy make walking seem interesting?
• When am I ever going to catch up on my book list?
• Should I put up Christmas decorations outside before the weather gets colder?
• Could burritos be more awesome?
• Should I go see the Stevie Ray Vaughn tribute show? By myself?
• Why don’t I play guitar more?
• Why is it I forget what I needed when I get to the store?

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3. Look for the X-hacker response header in HTML Headers section on the Net tab. It reads: “X-hacker: If you’re reading this, you should visit automattic.com/jobs and apply to join the fun, mention this header.”

This is my first blog post from an iPhone.

I woke up Friday and decided to skip the final keynote address and remaining sessions. I had a raging headache and was anxious to get home. I did a little shopping for Mother’s Day. Then I took the subway to the airport to see if I could catch an earlier flight. Unfortunately, I did not have luck and settled in for the four hour wait before my flight.

It was probably best that I did not good back to the convention center. I probably would have bought another book from the bookstore. Here is a list of books which I bought while at JavaOne:

• Think Better by Tim Hurson
• The Pragmatic Programmer by Andrew Hunt and David Thomas
• Effective Java, 2nd Edition by Joshua Bloch
• Prototype & Scriptaculous in Action by David Crane and Bear Bibeault with Tom Locke

Yesterday the headache returned. I spent most of the day taking it easy including a three hour nap. When I finally checked my email I saw this notice:

I feel much better today. I am catching up on chores and preparing for my week. I am looking forward to discussing some of the interesting things I saw with coworkers and friends.

Well folks, this is gonna be a short entry. Tomorrow is the last day of JavaOne. I need to pack up all of my stuff and swag in order to be check out tomorrow.

I dug the session on Nimbus. Vector-based UI components for a cross-platform look and feel just makes sense. The presenters showed off a nifty tool to design new vector-based components. Impressive stuff. I am anxious to download Java 6u10 and tinker with this. I am especially interested in reviving an old drum machine project I started writing in Gnome/GTK. I think I can utilize the customization available in Nimbus to make a custom, professional looking interface without the ugly hacks I had to use for GTK.

The Scala session made me want to puke. The presenter proudly proclaimed that the language is the next generation of Java and that it is everything that Java should be. I almost walked out when he said that they removed the “break/continue” mechanism in favor of “goto”. WHAT?! I decided to stay for the rest of the session to give the presenter a chance to redeem my opinion of my language. No luck. I was not impressed. So friends, I flipped the bozo bit for Scala.

The Filthy Rich Client session was great. It really got me thinking. Last year I wrote an app that animates dots starting at the top of the screen and falling to the bottom. The problem is that I hit barrier where it would not run faster than 30 fps. At the beginning of the session they demonstrated bouncing balls app that ran at over 100 fps. They explained the issues with Swings timer thread. I am hopeful I can revisit the app and get it working at a respectable framerate.

The session on Unit Testing with Groovy gave me a bunch of ideas I plan to take back to work with me. I talked to some guys who commit to the Groovy project about how we can work about issues we have with testing singletons. They gave me an idea or two to try out.

The Java Posse guys gushed about Scala in their session. The session was fun but not great. It made me nearly regret my decision to skip Sun’s After Dark party where the band Smash Mouth performed.

Overall it was the best day yet. I may not post the next blog entry until Saturday. I will be traveling tomorrow for over six hours and will be crossing two timezones. California was okay but will be happy to return to the familiarity of Illinois.

Ok, I just got back from the Sun Developer Network Party. I am going to make this short. My plan is to revisit these blog entries once Sun releases the videos and slides from the JavaOne sessions in the near future. Here’s my brief recap of today’s fun.

First of all, Scott Davis is a brilliant speaker. I highly recommend his Groovy: the Red Pill presentation. I missed this one at No Fluff, Just Stuff a few months ago. You will not look at the EXPANNNNNNNNDO-METACLASS the same way again.

The Struts 2 presentation flew over my head. I wasn’t sure if it was my relative lack of experience with Struts 1 or the presenters lack of examples. When the speaker pronounced HTTP as “Haytch Tee Tee Pee” it pulled my mind out of any comprehension of any point that he attempted to be communicated. This session was a waste.

The OpenSocial Container presentation discussed a project named Shindig. One of the presenters started working on his Web 2.0 social network website in January and finished in April. Am I in the wrong business?

I cannot wait for the Compelling User Experience session to make it online. Nothing was sacred. The presenter threw stones at a lot of today’s paradigms. I couldn’t agree with him more!

The video games BOF introduced me to the javagaming.org forum.

The Groovy in a Cloud session got me to thinking about the benefit of deploying virtual servers much more quickly than it would take any corporation’s purchasing department to acquire the equivalent hardware.

The GWT and Comet session introduced me to the Grizzly Comet project which uses continuations to push data asynchronously from the server to the client. Imagine an auction website where an auction’s high bid is updated automatically on your web page without having to refresh the page. Who knew it was possible to suspend a browser’s session?

The Groovy Builder session discussed making Domain Specific Languages (DSLs) with a part of the Groovy language with which I am not yet familiar.

Ok, friends, more later.. Off to do a bit of reading before turning in.