I am working on a hobby project where I aggregate feeds from several different sources. With the blogs I work it right now, it often happens that an author posts the same post to a few different sites. However, because of site formats and sometimes also quick edits an author makes on one site but not on the author, the article contents are usually not identical strings. So I needed something that would help me figure out whether or not two strings are nearly identical.

After Googling around and finding things like the xdiff extension and soundex, he discovered the two functions he needed - levenshtein and similar_text.

I am still trying to figure out which percentage will catch the duplicates but not catch too many posts which are only similar but not actually duplicates, but with the above 75% I seem to catch quite a few duplicates so far.

This series is not meant to be complete but some personal choice, these blog postings are also no replacement for documentation, but just pointers. My goal is that you try out 5.3 right now so we can fix bugs as soon as possible before releasing it The NEWS file has a quite short entry for my first subject: Added fileinfo extension as replacement for mime_magic extension. (Derick)

He looks at one situation where the extension could come in very handy - getting the content type of the file for a download push - as well as why its better than the older mime_content_type function.

Zend_Db is a layer which sits above the native PDO database extension. Before PDO (pre-PHP5.1) all we had to connect to databases were libraries that were developed in individual cycles and development teams, with little regard to what other database extensions were doing.

Taking this speed benefit of using PDO to do a majority of the work, PDO wrapper libraries like Zend_Db can supplement PDO with their own wrapper code leaving you with a fairly lightweight yet feature-rich database abstraction layer.

Aaron looks at connecting to a database (using both the PDO and DSN connections) and some example code showing how to work with the database using them - including queries and using transactions.

Managing configuration is a pretty simple thing to do in PHP, in fact, I'd bet that at some point in their programming career every php programmer has written code. But as soon as you get a bit bigger you realize that you're going to have trouble accessing your configuration variable.

There are many reasons to manage your configuration data indepenantly from your business logic. One common reason is that you don't want to enter your configuration data into the public versioning system that you use.

Aaron looks at how you can use the component in your application easily including an example using the built-in inheritance functionality to easily manage a move from development to production.

Caching isn't one of those things that many people think of when designing their first applications. However once they launch their new AJAX enabled web2.0 application, they might start wondering what they can do to get this beast to move faster. The answer is caching.

Aaron Wormus gets started with the basics - why use caching and some of what it's for - before getting into the actual code example. His simple example just shows how to cache a bit of information and get when it was cached. He also talks about implementing tagging for more complex caches (different pieces for different times), and the drivers that are available for the component - both frontend and backend.

Zend Framework looked like an interesting platform, but each tutorial that I read started out with explaining how to set up your front controller, and moved form there into writing an entire application. I am not starting any new projects, and have no need for that.

Instead, he's chosen to look a bit "behind the scenes" at what really makes the Framework tick and why it would be a good choice for any number of web applications out there. It's going to become a series on the ZDZ, so he starts it off right with a comparison between PEAR and the Zend Framework, specifically when it comes to error handling.

It's more of a compare and contrast kind of thing than a contest, but it does seem that Cal favors one's approach a bit more. Which one? Well, you'll just have to go read and find out...