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Sorry I've been quiet for the past few days. My Flex adventures took a quick detour through the massive land of our AS400 and DB2. Now that I had a prototype of my pretty line, bar, and pie charts I needed some real data. My job was to write a process to fetch our sales data from the AS400 server here at work nightly and populate some SQL Server tables with it. Easy Peasy, I thought. I didn't know what I was in for.

I am writing some SQL to pull data from our AS400 here at work. I was getting the error "Arithmetic overflow error converting expression to data type datetime." from the following code where date_column contained a date formatted like 20080930: year(date_column) At first, I thought there was some bad data in the column. It turns out, the datatype was int as opposed to varchar like I had assumed. This fixed it: year(cast(date_column as varchar(8)))

So in the past 3 days I have been trying Flex I've had several out of memory errors that crashed my browser. I don't know if it is my operating system, my browser, Flash in general, or Flex, but it sucks. For the record I am using Windows XP Pro, IE 7, Flash 9, and Flex 3. This is what happens: As I develop, I keep hitting save in Flex Builder, waiting for it to recompile in the background, then Alt-tabbing over to IE and whacking F5 to refresh. Well, over the course of 2 or 3 hours of doing this, the memory usage for iexpolore.exe just keeps climbing and climbing as though there is a memory leak or garbage collection isn't happening.

Flex objects extending the UIComponent class have two events that fire during their creation process. The "initialize" event fires when the object is starting to be created, but before its children are created. "creationComplete" fires after that object and all its children have been created. There is a great post and example here. I found this out while trying to figure out an intermittent error I was getting when loading my Flex app that was related to trying to access an object prior to its creation.

Well, to add to my list of interesting errors encountered with Flex; yesterday I started getting a JavaScript "Permission Denied" when I tried to run my app. The app would run fine but I would get that error every time the page loaded. After commenting out a bunch of stuff, I realized it had started when I added the mx:TabNavigator tag. I finally traced the error down to some JavaScript in the history/historyframe.html file which controls deep linking.

Wow, I don't know if I have ever been so happy to get such a simple piece of code working. I have jumped into Flex 3 with basically no knowledge in order to make some charting functionality and I can confirm that I hate learning new stuff. I mean, I love it AFTERWARDS; but that time at the very beginning when you don't have a clue why your code won't work, Google isn't your friend, and you swear you're the first person in the world to have just received that weird error message-- yeah, that is the part that sucks.

There has been a lot of talk recently about design patterns aimed at circumventing the overhead ColdFusion imposes upon us when creating CFCs. I'm not sure who coined the term "Object Instantiation Penalty", but the first reference to it I can find in the CF community was over at the Dot Matrix blog. Everyone seems to agree that object creation in ColdFusion leaves something to be desired, but I haven't seen anyone really quantify the price yet. I decided some line charts were in order.

I can never find this stupid page when I need it, so I am linking to it here so I won't lose it again. Use this when you want to download a specific JDK from Sun's site and don't want to wade through their confusing-as-heck "featured downloads" mess. http://java.sun.com/products/archive/ Update-- the URL appears to have changed. I'll put it here in case they ever deprecate the old one. http://www.oracle.com/technetwork/java/archive-139210.html

The other day I was writing a wrapper CFC to consume a web service, and return the results. Several of the web services' method returned arrays of structs and I was in the mood to experiment, so I decided to have my CFC present the data back as an array of components. I knew that there would really never be more than 20 or 30 objects coming back so the cost of object instantiation wouldn't be a big deal. There were 7 different "types" of objects coming back in the various method containing mostly strings and an occasional binary image. I didn't want to do all the typing so I decided to toy with Object Synthesization similar to what Peter Bell has been talking about.

Well, I'm settling in to my new job and today my boss showed me an old third-party app they have which shows a dashboard of bar charts outlining the companies progress. It's a nifty little program that lets you drill down into the data and choose different graph types. They wanted to do a face-lift on the graphs, add a little more functionality, and make it web-accessible so it could be viewed remotely. It didn't take me long to sell him on the charting package built into Flex 3 Professional.