I’ve been working on BUG#17928, which is all about “testBackup fails in error handling testcases” which appeared after we merged in some work to the 5.1 tree (which is okay in 5.0) that changes some things in the way that online backups are done in NDB to better support recovery in the event of various types of failures and various times in the process.

Anyway, not all systems are affected by this bug… I’m at least reproducing some of the failures on my laptop and have spent the past while in the depths of the BACKUP and NDBFS blocks trying to work out what’s going on and why we’re hitting this assert.

NDBFS is an interesting block as it’s the file system interaction for NDB - so we’re doing things that could take an arbitrary amount of time. We don’t like waiting for those sorts of things in cluster, so we go on and do other work.

…

I’ve decided to affectionally call the MySQL Workbench Product “The Anaconda”. It’s been a wrestle so far to get all the features and functionality I wanted in this product. Of course I’d much rather have seen this product at say version 0.5, or 0.6, as I would not feel as guilty towards my comments of a 1.0 product when I’m having issues. I also have great respect for Mike Zinner and this small team of GUI developers that are developing and supporting the MySQL GUI products. Nevertheless, here is my latest round of analysis of the product across various platforms.

Hardware

Machines

1. Dell Inspiron 5150 P4 3.2GHz 1GB RAM, 80GB & 120GB HDD
2. Generic Desktop PIII 866MHz
3. Dell Inspiron 500 PIII 600MHz

Operating Systems

For the purposes of these tests I’m going to run multiple OS’s installed on seperate drives to attempt to isolate and reproduce …

My work life is really fragmented at present, so I’ve decided a split approach in answer to Dave Rosenberg’s How I Work–what I have learned so far .

CentOS 4.3
FireFox 1.5, ThunderBird 1.5, Gaim, SSH, Skype, Open Office 2.
Maybe not all of these every day, but some combination of each day –> MySQL 4.1, MySQL 5.0, MySQL 5.1, MySQL Workbench, Eclipse 3.1, J2DK 1.4.2, J2DK 5.0, Apache Tomcat 5.0.28, Apache Httpd 2.0.53, JMeter.

Presently also configuring a new laptop drive running …

I’ve been using VNCViewer from RealVNC under Linux to remote connect to an older machine running windows. Two reasons, I don’t need yet another screen on my desk, and I need windows to adequately test and use the MySQL GUI products, in particular MySQL Workbench.

I never realised there was a better way, particularly over a local network, a command called rdesktop which is capable of natively speaking Remote Desktop Protocol (RDP).

$ su -
$ yum install rdesktop

This did only give me version 1.3.1. The current version 1.4.1 available from the rdesktop Website does provide greater commands including the syntax I use.

su -
cd /src
wget http://optusnet.dl.sourceforge.net/sourceforge/rdesktop/rdesktop-1.4.1.tar.gz
tar xvfz rdesktop-1.4.1.tar.gz
cd rdesktop-1.4.1
./configure
make
make install …

As part of both my UltimateLAMP side project, and my greater involvement with MySQL Workbench, I’ve been wanting to review and document the database schemas of Open Source products.

Indeed, as part of discussions with Mike Zinner of MySQL AB at the recent MySQL Users Conference, I suggested an idea used in the Java World, for example by Clover and Agitar, where to promote the usefullness of their respective tools (in this case code coverage), they provide results against Open Source Products. For an example check out Clover Examples.

With MySQL Workbench, to get some greater …

DaveM talks about Ingo’s new SMP lock validator for linux kernel

A note reminding me to go take a look and see what can be ripped out and placed into various bits of MySQL and NDB. Ideally, of course, it could be turned into a LD_PRELOAD for pthread mutexes.

Anybody who wants to look deeper into it before I wake up again is welcome to (and tell me what they find)

I am looking for a job starting this fall. By that time I should also hold a degree in computer science from the TU Berlin. My tasks on the job should be some how at least partially connected to open source and covering at a minimum 2 of the following 3 fields of expertise (in order of most preferred):

• SQL RDBMS like MySQL, Oracle, SQLite, PostGreSQL (especially portability and migration)
• Community Relations (helping companies work with people from the community and vice versa)
• PHP (preferably database driven intranet applications or frameworks)

I would prefer to be able to stay in Germany, specifically Berlin. Though its all a question of finding the right place and challenge. For example I have no problem telecommuting from home with occasional trips to an office; even for a few weeks now and then with a sleeping bag. Actually I …

Here are some steps involved. Using the current MySQL defacto engine InnoDB. Of course, Falcon, PBXT and others will enable alternative engines to be used.

Convert Table Storage Engine Types

$ mysql -u[user] -p[password] [database] -e "SHOW TABLES" | grep -v "Tables_in" | sed -e "s/^/ALTER TABLE /" | sed -e "s/$/ ENGINE=InnoDB;/" > upgrade.sql
$ mysql -u[user] -p[password] [database] < upgrade.sql

NOTE: This may not work for all tables, for example those with FULLTEXT indexes will fail.

For the introduction of Referential Integrity we need to ensure the following.

• Each Foreign Key column should have an index. Prior to 4.1 I think this was a requirement, however it’s a good general practice regardless for SQL performance.
• The datatype must match between Primary Key and Foreign Keys. The most obvious oversight is normally UNSIGNED, however you also for example have INT …

Following my implementation of UltimateLAMP, read heaps more at this thread, I undertook to provide customisations of a MediaWiki Installation. Here is the first lesson that you can undertake if you wish to beautify the default MediaWiki Installation.

For the purposes of this demonstration, I am going to help out Jay & Colin and propose a restyle the MySQL forge to fit in with the default Home Page. Hopefully you will see it there soon!

For the full lesson Read More Here

Lesson 1 - Updating the default Monobook.css

There are several different ways to make style changes, the simpliest is to customise the system …

I won an iPod at php|tek. Since Apple does not support Vorbis Ogg my options were either to install some third party firmware or to sell the iPod. I went with option #3 and gave it to a friend of mine who is moving to South Africa for an internship that will have him traveling a fair bit. Since he is still using mp3 he got it as a farewell present. Now other friends have noted an interest in iPods as well. Since apparently outside of IT iPods giveaways are less common I will try to get each of them an iPod with my awesome computing skills (Ok, I won the first one with drinking alcohol, but I still have not really acquired the taste for drinking so ..).

Anyways the purpose of this post is to highlight some issues in MySQL that will hopefully get fixed in …