Vitor Rodrigues

>> doc.find('/*').first.name
doc.find('/*').first.name
=> "Customer"
>> doc.find('/Customer').first.name
doc.find('/Customer').first.name
NoMethodError: You have a nil object when you didn't expect it!
The error occurred while evaluating nil.name
	from (irb):52

Something is wrong with Ruby’s libxml xpath evaluator. I’m only able to use the wildcard * to select elements and not the element’s name. After doing some research on the project’s page, there are 2 comments about the problem, complaining that libxml’s support of XPath is just too limited and it has lots of problems when dealing with namespaces. Default namespaces are not parsed, namespace wildcards are not supported and namespace prefixes won’t work all the time. What’s the advantage of announcing a 300x faster xpath speed than rexml when it doesn’t work and valid xpath expressions return syntax error?

>> doc.find('/*:Customer').first.name
doc.find('/*:Customer').first.name
XML::XPath::InvalidPath: Invalid XPath expression
	from (irb):73:in `find'
	from (irb):73

It’s time to go back to the slower but working rexml.

Popularity: 9% [?]

If you happen to be using Ruby in Windows and need to use libxml and don’t feel like compiling it from the source code, here is an alternative. Charlie Savage did the work himself and provides the binary that you can use instead of compiling your own.

Popularity: 5% [?]

Antonio Cangiano is one of of the persons involved in the creation of a Ruby and Rails native adapter and vendor supported driver for DB2. He now has a post in his blog requesting comments on Python and Django APIs for DB2. 

If you use Python or Django with DB2 and would like to make comments that will help creating a high quality DB2 adapter for your programming language, this is your opportunity. Even if you don’t use DB2 yet, but have knowledge on Python database application development, I’m sure you have lots of ideas you would like to contribute. Stop by Antonio’s blog and leave your comments.

Popularity: 10% [?]

Popularity: 3% [?]

After a few weeks of wait, I just got my Joost beta test invitation. It was bellow my expectations.

I don’t have a TV, so I’m an avid consumer of TV Shows available on the internet (OVGuide and TV-links are great sources) and was expecting Joost to providing me something more than just a very small catalog of recorded shows. 

Good Things:

Not so good things:

Although many P2P TV programs have been around for a long time, it’s very likely that Joost is the only one with legal rights to broadcast all of its contents. That may be the reason why there are so few choices available for now. Let’s wait that someday we will be able to watch LOST, Heroes and CSI in Joost

I’ll wait for the weekend to explore it better and maybe add some more comments about it.

I don’t have any invitations to offer yet, but feel free to leave a comment and I will send you an invitation when they become available.

Popularity: 3% [?]

Some of us have been using opensource software for a long time, but how many times have we contributed back to the community? Indeed, it looks much simpler to use a product than to help developing it. However, sometimes this is not the case. There are a lot of projects out there waiting for our help. So, if you feel it’s time to give it back to the community, here are some ways to do it:

• open bugs when the software doesn’t work. Don’t just quit using the software because it doesn’t work properly. Open a bug and you will see that eventually it will be fixed.
• if you have the know-how or the will to do it, fix the bug by yourself and submit your patch, either to the mailing lists or attach it to the bug report.
• subscribe to the mailing lists of the projects you are interested. Soon you will find yourself giving your opinion and suggestion and thus contributing to the project.
• if stability is not a major concern for you, keep updating your software to the latest version and give your input back to the developers.
• help developing new features. Often opensource projects lack new features because the lack o resources to develop them.
  

So, you still think you cannot help because you are not a developer, or you don’t know the programming language being used by the project you want to help? Projects need help in many other ways other than developing code:

•  you can help with translations. Translate it to your own language, or if a translation already exists, review it to ensure accuracy.
• help writing and reviewing the docs.
• you can help by just being a test user and reporting back the problems.
• help maintaining website, moderating forums, etc..
  

Do you feel the urge to help? A good place to start is sourceforge.net. Besides the thousands (or even millions?) of projects that you can browse trough, there is a “Help Wanted” section, where you can see all the requests for help from projects being hosted at sourcefourge. From help with design, to development and documentation, I’m sure you will find something that interests you. 

Popularity: 4% [?]

Popularity: 7% [?]

Gimp 2.4 will have a new feature called Perspective Clonning. This tool is already available in Photoshop CS3 and it allows you to clone part of your picture maintaining the perspective distortion of the subject.

This feature was developed by Pedro Alonso as one of GIMP’s projects for Google Summer of Code, and you can find some video tutorials and examples on his website. I gave it a try, and the result was this:

Very neat tool indeed!

Popularity: 12% [?]

It is a generally accepted idea that Apple has a fantastic marketing team. We see their ads, their launch parties, their website, their design, and we almost want to buy the product just because it looks cool, nice and great, but we didn’t even try it yet. Today I was surprised by another company’s marketing ideas. Believe it or not, it was Microsoft and it’s Vista marketing campaign! I should say that I know nothing about Vista, besides the fact that was launched this week and that was being developed for a long time. I still have no curiosity in learn about it or its new features, since I don’t plan to use it in a near future.

To the official Vista’s launch in Toronto, Microsoft built a very cool ice house. The house has been a huge attraction in downtown Toronto, and the house visitors have the opportunity to see the the new msft OS and Office packages in action. This was a great way of calling people and try to impose the “coolness” factor. I checked the house today from the outside and it looks cool. I will try to visit the inside part tomorrow to see how does a ice toilet works!

Despite the factor of the ice house being a huge attraction by itself, the location chosen (the same used by Sony for the recent launch of the PS3) was also very good. It was just outside the main entrance of the Toronto Eaton Centre, that is just the biggest shopping mall in Toronto (and the 3rd biggest in Canada), and currently Toronto’s top tourist attraction regarding number of visitors. What best location can you have to demo a product than a place where all the families go and most of the tourists also go?

After checking out the ice house, I decided to stop and the Indigo store inside the mall to read some magazines and look at the bargain books (sometimes you find really great value in there). And what was my surprise when I looked at the “Hot & New” section at the entrance, and it was all about Vista! There were more than 10 different books on Vista, from the Bible to the Idiots series. That I was not expecting, but I should say that it was also a good strategy. While I was reading a magazine close to the Vista stand, I would see people stopping and looking at the Vista books with plenty of interest and commenting about it. They definitely caught people’s attention to their product launch.

And at the end I came home thinking: if only Linux had an opportunity like this…

In other news: I gave a try to GIMP 2.3.14 and it rocks! Some very good new features. More on that soon.

Popularity: 5% [?]

The most common way used to generate and retrieve access plans in DB2 is by using DB2 Control Center. CC provides a graphical representation of a query’s access plan, and it also includes an Index Advisor, that you can use when you are not sure about which indexes to create and to use.

However, not always you have access to a graphical environment (needed to run DB2 Control Center). For the command line, there are two utilities that you can use. DB2 EXPLAIN command and the db2exfmt utility. Although the first one is more complete, I find the second one to be easier to use. So, in order to get an access plan for your query using db2exfmt, you just need to do:

PS: don’t forget to run "db2 set current explain mode no" when you are done with your access plans, so the queries will be executed. 

Popularity: 10% [?]