Over the last little while I've come across quite a few XML feed generators written in PHP, with varying degrees of 'correctness'. Even though generating XML should be very simple, there's still quite a bit of pitfalls I feel every PHP or (insert your language)-developer should know about.

1. You are better off using an XML library

This is the first and foremost rule. Most people end up generating their xml using simple string concatenation, while there are many dedicated tools out there that really help you generate your own XML.

In PHP land the best example is XMLWriter. It is actually quite easy to use:

 
$xmlWriter = new

If you’re like me, you’ve gotten tired of writing endless test cases for parsers that can understand the thousands of variations of text output by SHOW INNODB STATUS. I’ve decided to solve this issue once and for all by patching MySQL and InnoDB to output XML, the universal markup format, so tools can understand and manipulate it easily. Here’s a sample snippet:

<status><![CDATA[
=====================================
100320 15:46:24 INNODB MONITOR OUTPUT
=====================================
... text omitted, but you get the idea ...
]]>
</status>

PS: Yes, this is a late April Fool’s joke.

Related posts:

XML output from mysqldump

I’ve been using a lot of RESTful services these days and have been waiting for a good book that is dedicated to the topic. I recently received a copy of ‘RESTful PHP Web Services’, which does a successful job of outlining proven concepts in current web technology. If you want to learn the methods for creating and consuming RESTful services then you will find many examples in this book. From the architectural plans to well thought out code samples, the book covers a lot of ground in a relatively quick read.

The first chapter gives the reader a quick introduction to RESTful services and the most common PHP frameworks in use at the time of writing. I particularly enjoyed the section on the Zend framework due to

Rome is a great city and it will host a bunch of great people (including me ) at November 12-13. This is when the second IKS Project workshop will take place. The goal of this workshop is to start working on an Open Source software stack that allows other Open Source projects and software vendors to leverage semantic search technologies.

IKS is an EU-funded project with an overall budget of 8.5 million Euros. The first workshop back in May saw two dozen of bright Open Source CMS minds discussing a semantic stack in general. This time, it will also make sense for non-CMS-related Open Source projects and vendors to join.

There

This is a basic heads up post, perhaps even blatant self marketing. So, please continue reading.

If anyone recalls the website http://mysql-dba.com they would know that it’s based on the planet.py codebase that is written in python. I originally wrote a simple php script that utilized the lastRSS.php class for parsing feeds on the backend for archival purposes to be used at a later date. I say archival and later date because the site itself did not utilize any of the relational data storage to run the site. The site’s python code and cache was updated by cron scripts every 15 minutes and new data was scp’d from my dev server to my webhost’s servers.  This process eventually was quite randomly run since my development server rack in the garage at home gets really hot during the summer months

Download MySQL Cacti templates

As promised, I’ve created some improved software for monitoring MySQL via Cacti. I began using the de facto MySQL Cacti templates a while ago, but found some things I needed to improve about them. As time passed, I rewrote everything from scratch. The resulting templates are much improved.

You can grab the templates by browsing the source repository on the project’s homepage.

In no particular order, here are some things I improved:

• Standard polling interval and graph size by default.
• Full captions on every graph; you don’t have to guess at how big the values are. Each graph has current, max, and

Today I was asked a question about defining custom extensions for vim syntax highlighting such that, for example, vim would know that example.lmx is actually of type xml and apply xml syntax highlighting to it. I know vim already automatically does it not just based on extension but by looking for certain strings inside the text, like

After digging around I found the solution. Add the following to ~/.vimrc (the vim configuration file):

1
2
3

syntax on
filetype on
au BufNewFile,BufRead *.lmx set filetype=xml

After applying it, my .lmx file is highlighted:

As a I wrote a couple of days ago, I went to the second day of PostgreSQL Conference East 2008 last Sunday. I had a good time and really enjoyed meeting everyone, listening, learning, and occasionally talking. I asked a number of fearless-newbie questions that paid off handsomely: people were very willing to humor me. I also left with a beautiful t-shirt, mug, and bag combo thanks to EnterpriseDB. The bag has already been put to use for a grocery shopping trip.

Note to conference/website organizers: I can’t link to anything but the front page, so I assume my link above will someday point to the 2009 conference, or the 2008 West conference. It would be good to give

I was browsing around the web and ran across this article at xml.com, XML Moves to mySQL. Being a heavy XML user, I had to read the article. It looks like MySQL is expanding the built-in support for XML.

This article isn't very detailed but it links to Using XML in MySQL 5.1 and 6.0 at mySQL.com which is very detailed.

I like the ability that is built in to support loading XML from files. That's a feature I wish Oracle would work on. Even in 11g, that functionality is still limited.

MySQL also adds ExtractValue() and UpdateXML() support. If you're manipulating XML much, you know that these two functions are needed.

From what I know of MySQL and

I was very pleased when I heard about Oracle adding pivot functionality in select statements. Finally — we wouldn’t have to copy the data to a spreadsheet or code a ton of sum(case when col1 = 'X' then amount else 0 end) total_X for each column we would want to display.

I am basically looking for three things in a pivot-style query:

The first item is the only one that really matters. I can work around the other two, so let’s get started.

Create a test table with a few rows:

create table bob_pivot_test( id number, cost number, tx_date date, product_type varchar2(50));
insert into bob_pivot_test values (1,10.99,sysdate-10,'Toy');
insert into bob_pivot_test values

I'll be speaking on using Drupal with Adobe technologies such as Flex, AIR, and Flash. The event is totally free but you must register.

DrupalCampLA - http://upcoming.yahoo.com/event/221082/

select xml_tag('table',null, concat(xml_attr('name',t.table_name),

xml_escape(value) replace characters not allowed in xml with the escape sequences
xml_attr(name, value) create an xml attribute
xml_tag(tagname, tagvalue, attrs, subtags) create a tag, optionally with

select xml_tag('table',table_name,null,null)
from information_schema.tables
where table_schema = 'INFORMATION_SCHEMA'

Here's the AJAX prototype example that I used in my AJAX presentation today.

I wanted to give an example of a good use of AJAX, and at the same time keep it simple. So I thought a good example would be to build a zip code verifier. As soon as the person enters the zip code it makes a request to the server to see if the zip code is in the database, and returns the city and state.

So the user first sees this:

Once the zip code is entered, and the response received it looks like this:

If the zip code is not found in the db:

Ok, now lets build it...

Download prototype, and a zip  [Read more...]