This topic may look boring and obvious but it is extremely important for MySQL Performance Optimization. In fact I probably have to touch it in every second MySQL Consulting work or even more frequently.

IO Bound workload is quite different from CPU bound one, which happens when your working set (normally only fraction of your database) fits in memory. What is fast when data is in memory can be extremely slow if it does not. For example if you have the query which analyzes 10000 rows it often would take fraction of the second with fully in memory workload, however if you would need to go to the disk, lets say even only in 10% of the cases and so perform 1000 possibly random reads you will have query taking at least 5-10 second, or more under the load which is already way more than you should target for web applications.

So designing your application …

When I transferred the content of mysqldevelopment.com over to the MySQL Forge site I always intended to continue updating this blog. Unfortunately due to work commitments I simply haven't had the time and because I haven't been working with MySQL so much I also haven't had the quality of content I once had.

Rather unsurprisingly then I haven't been receiving much in the way of email to my email address andrew_gilfrin@mysqldevelopment.com. I have however been getting plenty of spam so I have decided to drop that email address, therefore if you wish to contact me you can do so at my hotmail address (andrew_gilfrin at homtail.com).

BadVista.org: FSF launches campaign against Microsoft Windows Vista, Free Software Foundation (Press Release)

Open Source Technology At The Application Layer A Key Focus At LinuxWorld OpenSolutions Summit, IDG World Expo (Press Release)

SpikeSource Appoints Three New Vice Presidents, SpikeSource (Press Release)

Free Competitor to Microsoft Office Releases New Version, OpenOffice.org (Press Release)

MontaVista and Atheros Deliver High Performance SDIO Stack to Open Source Community, MontaVista Software (Press Release)

…

Version 1.1.3 of Zmanda Recovery Manager (ZRM) for MySQL, an enterprise solution for backup and recovery of MySQL databases is available for download at Zmanda downloads page.

Changes since 1.1.2 release:
* Supports Ubuntu Edgy (6.10) release
* Works with MySQL enterprise 5.0
* User configuration for custom plugins
* Bug fixes

Documentation is available in ZRM for MySQL wiki. Please use forums to provide feedback on the release.

Thanks to all users for providing valuable feedback as well as finding bugs in earlier
releases

I sometimes see advice to do SQL date operations with the + and – operators on platforms where they are overloaded for date types. I try to avoid that, because it can give unexpected results. I prefer to explicitly use the built-in date/time functions. I’ll show you an example where the operators cause problems, but the functions do the right thing. My example is in MySQL, but it applies to some other systems too.

What is this - how you say - database transaction?

Remember back in college when we were taught that all "real" databases had transactions and foreign keys.

Remember when all those Postgress fanboys would make fun of anyone using MySQL because it was inferior since it lacked foreign keys?

Turns out they were all wrong.

Running without databases transactions can even be really fun. It's a bit like driving 120 Mph down the highway on a motorcycle without a helmet. Just don't crash and you'll be fine! This is how I stopped worrying and learned to love the auto commit.

With the recent Scaling eBay PDF I think we can put the final …

Useless Utilities #1

[Update 12/30/2006: Added Macworld Info and a Donation Button.]

[Update 12/20/2006: Added a small FaQ based on feedback.]

I created Keyboard Cleaner. It comes in handy when you want to clean your keyboard, but you are afraid you might trigger a command or change or delete some of your current work beyond repair and undo. Of course you could save and close everything. Sometimes however, it is just not what you want.

Enter Keyboard Cleaner. It shields your desktop and intercepts every keystroke you might accidentally make — except for Command-Q.

Needless to say that this was an educational project for me. While trying to create something like …

The MySQL Symposium will be organised from 5-7 March next year in Amsterdam

Next to me relating on my experiences with Cluster , there will be a lot of interresting speakers such as David Axmark , Ann Harrison , Mike Kruckenberg , Peter Zaitsev , Lenz Grimmer , and others

This is the European MySQL event not to miss next year !

mysql podcast

This week’s feature talks about ACID compliance, what it is, and how MySQL achieves it.

If folks have ideas or suggestions for content, please let me know by e-mailing podcast@sheeri.com or by leaving a comment.

You can Direct download all the oursql podcasts at:
http://technocation.org/podcasts/oursql/

Direct play this edition at:
http://tinyurl.com/yy7pgz

News
Download MySQL Turbo Manager Free Edition at: http://www.mentattech.com/themes/mentat/download.html

Wireless …

I’m involved in the authoring of two books at the moment - both using different tools, neither of which would be my choice if it was up to me. One is using DocBook, writing raw incredibly verbose XML… which honestly, isn’t that much fun. The other is in Microsoft Word (well, OpenOffice.org Writer for me). The last time I really used Microsoft Word really seriously was probably around 1998/1999 with Office 98 on the Mac. It was a pretty awesome suite of software actually. Especially after the update that fixed a few crashing bugs :)

One thing I do notice though is the collaboration tools in OOo Writer are nowhere near good enough. The notes are small yellow rectangles where you either have to hold the mouse cursor over them to read them (ick, slow) or double click them and scroll right forever to read the whole or in conjunction with the last way, use the object browser.

Also, track changes doesn’t really …