For those that are using a Referential Integrity based Storage Engine in MySQL, the use of Foreign Keys can provide an extra level of data integrity within your application. There are of course caveats to this statement, such as correct design, proper transactional use etc, but that’s a topic for another time. The use of CASCADE has an effect on this.

So, just a quick refresher, using the MySQL Sakila Sample Database (if you don’t have it, get it. This can be a valuable tool in many other areas). Let’s first check out the Schema Diagram. We will …

I’ve yet to find any Java project that doesn’t have dependancies on some other Open Source external libraries. I’ve yet to find a Java project that manages these external dependencies appropiately for support and integration at an enterprise level.

As with most projects, understanding an applying sound principles that scale will help you at a later date, and generally the cost of implementation is minimual at the start, but of course becomes more expensive when it’s really needed. The classic case is Version Control. For over 10 years, even on small single developer projects, I’ve used Version Control, it should be taught at university as an introduction to good programming design, it would greatly benefit software development and maintenance.

Back onto the topic of hand. Let’s use a moderate Java Web Based application, and for the purposes of this discussion the following Open Source external libraries are incoporated. …

So,

http://www.mysql.com/training/certification/candidates.php?exam=core

has 233 names for the core exam, which has been out for a few years now. I passed it in 2004, and sure enough, my name is one of the 75 in the US. Are there really so few people out there, or are they just not taking/passing the exam?

I did notice at the MySQL Users Conference that only 1/4 to 1/3 of the exams earned a passing grade, and given that you have to pass 2 exams to receive certification, the chances of passing are not in your favor. Granted, studying helps (as does experience), which is how I passed the Core exam in 2004 and then both 5.0 DBA exams in April (2006).

Like much of the rest of life, it’s not difficult, you just have to work at it a bit. Read the certification guide, and study, and use MySQL, and you’ll pass.

I’m quite amazed at the low amount of people who are actually certified. I guess it’s better …

23rd Mostra - “Heroes in Tyrol”, by Niki List (Austria-Sweeden-Germany)

I managed to see most of this film a few years ago. Anybody know where or how I can get a DVD of it? (with English subtitles). I know somebody in the wider community has to know where (hence why i’ll put this entry in the MySQL category - i know somebody there has to know something about this film).

Besides - it has drinking songs, and MySQLers will get the connection.

Over at my junkcode section, I have mysqlbug.py which is a plugin for the GNOME deskbar panel applet.

If you’ve used Quicksilver on MacOSX, then you know the kind of app that Deskbar Applet is.

This one lets you type “bug 1234″ and be given the action of “open mysql bug 1234″. If you type “edit bug 1234″ it gives you the option of editing that bug number.

We’ll see if this proves useful.

Many thanks to kamstrup (one of the Deskbar developers) on #deskbar on gimpnet for helping me out with the plugin.

I totally heart Deskbar. It’s awesome.

MySQL Lists: commits: bk commit into 4.1 tree (stewart:1.2483) BUG#19894

The other day I committed this bug fix. A one bit patch. It is generally decided amongst the team that nobody will ever produce a smaller patch.

Growing up in the world of linux uptime was always considered a good thing. On IRC every once in a while someone would post an uptime. Everyone else in that channel would then check their uptime and if it was greater or close they would post it in the channel. Most of these systems were home linux boxes used for compiling random programs or maybe hosting a webserver for experimenting. It was fun to see how long we could keep them running for. Since those days I have come to realize that high uptimes are a bad thing.
Keeping a server up for months or even years means that you aren’t maintaining it. It hasn’t been kept up to date with new kernels that have fixes for security holes. It doesn’t have new packages or new tools that can help it run more efficiently and have features that can make using it easier. It’s also not up to date with new servers that are being deployed which means that people logging into your server with a high …

I have begun work on the next set of features for MDB2. I just implemented a feature inspired by the popular ADODB abstraction layer. John calls it smart transactions, while I am currently planning on calling it nested transactions. However I will wait until Lorenzo has some time to look at things to see if we can fit native nested transactions in there or not. Interbase/Firedbird really shines in this department.

I have written up a little script to show the current implementation available in CVS:

<?php

$mdb2 =& MDB2::singleton($dsn);

$mdb2->setOption('debug', true);

$query = "DELETE FROM autoinc";
$result = $mdb2->exec($query);

$query = "SELECT id FROM autoinc";
$result = $mdb2->queryCol($query);
var_dump($result);

$query = "INSERT INTO autoinc (id) VALUES (?)";
$stmt = $mdb2->prepare($query);

$mdb2->beginNestedTransaction(); …

Today, will go down in my professional history as quite possibly the lowest I would ever think of a software developer. I’ve carefully avoided the term “fellow coder”, speaking of a IT industry sticking by fellow IT people, but not today.

I presently support an existing production system, some 1000+ users that’s been in place around 3 years in which I’ve had no prior involvement until recently. Integration with other external parties within the system have provided an esclation in errors being reported in this external communication, and lack of adequate feedback to the user is another topic. Email is the means of reporting administratively of user errors, again another topic of issue. Within these emails, which are almost impossible to manage due to the limited internal GUI only toolset and lack of access to actual email account files to automate scripting (yet another topic? Do you see a trend here), is some relevent information …

Groggy mentions trying to draw sequence diagrams with pic. I recommend using Spinellis excellent UMLGraph toolset that he developed while writing Code Reading. That book was wonderfully inspiring to me, and helped cement my desire to work on open source software.

From what I remember, the sequence diagram stuff was a clever set of pic macros, so that you could just describe a sequence diagram and then generate the picture. I love having pictures to use during a discussion because they help avoid confusion, but I absolutely hate drawing pictures or using drawing tools - I prefer to keep the diagrams in plain-text, source code, in a revision control system. Using pic for the sequence diagrams fits the bill perfectly. Code is …