Weblog for the AMIS Technology corner
Archive for January, 2008
HOTSOS 2008
Jan 31st
The new year has started and one of the most important Oracle performance conferences is about to start. The Hotsos 2008 Symposium will be held again, almost traditionally now, in Las Colinas, Dallas, Texas. This year 3 AMIS colleagues, Gerwin, Patrick and I, will be attending this performance dedicated hotspot, from the second until the sixt of March. This years keynote speaker is Cary Millsap himself and I guess that I will really enjoy Thomas Kyte’s training day.
AMIS Query on Oracle Coherence
Jan 31st
Of all the new and exciting stuff I have seen at Oracle OpenWorld this year, two new technologies (at least to me) stand out. The first is CEP (Complex Event Processing), which I am sure will be covered in another post on this Blog in soon. The other is Oracle Coherence, known as Tangosol Coherence before Oracle acquired this technology recently. To describe what this technology is all about, lets start with a quote from OTN:
Coherence provides replicated and distributed (partitioned) data management and caching services on top of a reliable, highly scalable peer-to-peer clustering protocol. Coherence has no single points of failure; it automatically and transparently fails over and redistributes its clustered data management services when a server becomes inoperative or is disconnected from the network. When a new server is added, or when a failed server is restarted, it automatically joins the cluster and Coherence fails back services to it, transparently redistributing the cluster load. Coherence includes network-level fault tolerance features and transparent soft re-start capability to enable servers to self-heal.I don’t know what your impressions are after reading this, but my first thoughts were along the lines of: "Sounds like very complex cluster configuration and management, and probably it will be very difficult to program against". However, after listening to a number of excellent presentations on the subject, and after having downloaded and "installed" the software (you’ll find out why I put that between double quotes shortly), I can safely say that although nothing in the OTN quote above is untrue or even exaggerated, working with Oracle Coherence is ridiculously simple. 
Read the rest of this entry »
How to write a good incident description/file a clear bug report
Jan 31st
Issues are an important way of organizing tasks around both development and maintenance of the application as well as for collecting collective knowledge about the application and the use of the technology. To efficiently share the knowledge and transfer tasks between developers and other parties involved, it is important to create issues in a way that makes them complete yet concise.
I have been working on a fearsome number of issues lately. 
Read the rest of this entry »
Becoming a SOA Developer…
Jan 29th
One of the reasons why I have been very quiet lately on this weblog is the SOA Training Program we started at AMIS, two weeks ago. With 11 experienced developers – 10 from AMIS and one guest from one of our partnerts – we started an intensive training program with festive kick-off, including bubbles. Read the rest of this entry »
Running Internet Explorer 6 next to IE7 in standalone mode
Jan 25th
When I saw a meeting request called "IE6 vs Firefox" in my calendar I was preparing for a nice battle to make the interface of this project look the same in both browsers. On my machine, however, I am running IE7 (next to Firefox 2 of course) already for quite some time, so testing could be a bit of a problem. Luckily, there is such a thing as running IE6 in standalone mode, as I’m sure a lot of people already found out.
Like IE6 itself, this method is not without its limitations. On of the issues that had to be fixed was a rather common problem with IE6, and that’s the fact that it does not support transparent PNGs. Of course, there are several different solutions to this problem, either with javascript or just css with IE’s arbitrary conditional comments and behaviour files. These methods both rely on the DirectX filter called "DXImageTransform.Microsoft.AlphaImageLoader" for its alpha transparency. Both methods are tried and tested numerous times back in the days IE6 was still in its hayday (that must have been somewhere around 2001 ar about a century ago in computer terms). The standalone version of IE6 seems to lack some features the original built had, which includes the DirectX filters.
Thanks to some Googling I soon found out (site seems to have some problems) that indeed two dll are missing. The two files needed to get transparency filters working are:
- DXTMSFT.DLL
- DXTRANS.DLL
These files can be found at dll download sites like DLLdump.com, which come of course with no guarantee whatsoever. Put the two files in the directory where you put IE6 standalone. You can verify if your actions were succesful by visiting this page.
This solution requires only about 5MB to be downloaded, but does only solve this one limitation of running IE6 in standalone mode. For instance, it does not support cookies which can be quite troublesome if you need to test a system where you need to login and the sessionid is stored in a cookie for example. If you want to test your project on IE6 and have already installed IE7 on your machine you are not entirely out of luck. Microsoft provides developers with a free download of Virtual PC 2004 with an image of XP SP2 with IE6, including installers for IE Developer Toolbar and Script Debugger which is actually quite convenient to use as a testing environment.
Oracle buys BEA, Sun buys MySQL – it must be the post Christmas shopping season…
Jan 17th
It was serious business yesterday. Within 10 minutes I received word of the Oracle BEA acquisition and the Sun MySQL take over. That was a lot to take in – for both Oracle and Sun, but for me also. What is happening here – and what will the consequences be. For customers, the industry as a whole, other vendors and last but not least my company and myself. Read the rest of this entry »
Puzzelen met SQL: Crash SQL Investigation
Jan 16th
door Anton Scheffer en Alex Nuijten
Dit artikel is de on-line tegenhanger van de rubriek Puzzelen met SQL
die verschijnt in de Optimize, het vakblad voor Oracle ontwikkelaars in
Nederland.
Deze
puzzel is gebaseerd op het verhaal van Carel-Jan Engel tijdens een AMIS
Query over High Availability. Hij vertelde hoe hij actief was bij het
vliegveld van Dresden in een periode dat daar een belangwekkende zaak
speelde: er waren in een jaar tijd meer dan 80 ongelukken gebeurt op de
snelweg naast het vliegveld. Dit was in de periode nadat er een viaduct
over de snelweg was aangelegd waarover vliegtuigen van de gate naar de
startbaan konden taxiën – bij vertrek – en van de landingsbaan naar de
gate – bij aankomst.
Het
verhaal dat al spoedig rondging, was dat de ongelukken dus wel het
gevolg zouden zijn van het viaduct: automobilisten zouden door
vliegtuigen op het viaduct worden afgeleid en vervolgens een ongeluk
veroorzaken. Het klonk best aannemelijk – maar klopte het ook?
Use BPEL Correlation Sets for repeated (synchronous) access to long running BPEL processes
Jan 14th
Standing on the shoulders of Anthony Reynolds and Matt Wright, I finally managed to get the Correlation Sets feature in Oracle BPEL PM to do what I intended: I can instantiate BPEL process instances, with an identifier of my choosing and immediately receive their first response. Then at some later moment in time, I can invoke one of these already existing instances to return the same or additional data to me. I can use these instances as a temporary data cache, as the foundation for a RESTFul WebService or allow them to collect data at their own pace, with me regularly checking up on them. Anything really I might want to ask a BPEL process at some later point in time can be made accessible in this way. And now that it works, it is all so very easy.
The steps are: Read the rest of this entry »
Scribbling the Contact Lenses Order/Collect Business Process (ready for BPEL?)
Jan 9th
I use contact lenses. A pair will last me a month, then should be chucked away and replaced by a fresh pair. I buy them in six-month packs. From time to time I have eye difficulties and may wear my glasses for a few weeks. Sometimes I forget to replace the lenses after a month and use them for six weeks. Read the rest of this entry »
Scribble on a Pull-turns-push architecture based on http – registering web applications as event listeners
Jan 8th
Today in the car I had some thoughts on applications working together, across the boundaries of technology and organizations. I tried to find an easy, cheap way for for example web applications to keep tracks of events of interest happening around it. No need for expensive, fancy or complex SOA, JMS, ESB etc. infrastructure. Read the rest of this entry »
