So, I recently ran into one of those situations where a customer complains that his MySQL database is slow, and “it worked great until about two weeks ago”. The first thing I look at in these situations is not the queries or any code, but the indexes. Once I determined that the indexes were almost nonsensical, I had a look at the queries themselves, which proved that the indexes were, in fact, nonsensical. Running the queries as written in the code, from a mysql shell, with EXPLAIN, I was able to further confirm that the indexes (most of them, anyway) were never used.

Easy right? Just reindex the table!

NOTE: I’m going to skip the talk about all of the database design issues on this gig and just go straight to solving the immediate problem at hand. Just know that I had nothing to do with the design.

But, supposing this table has 15 million rows and is running on a machine with 2GB of RAM and only …

My presentation, entitled “MySQL for non-DBAs” went well…considering the very broad topic and that the laptop I was going to present from decided to have a hissy fit. It was my work-sanctioned XP Pro laptop and the registry decided to corrupt itself, causing it to reboot over and over and over and…. Oh joy! Luckily, the group organizer allowed me to borrow his Mac and since I had the presentation on a USB drive (OpenOffice.org format, of course) we were rockin’ and rollin’ in no time.

I took the “MySQL 5.0 for DBAs” course last year. That was a 5-day course that used over 220+ slides. I compressed over three quarters of that content down to about 40 slides for a 2-hour talk with some live demo work thrown in for good measure. It was a tough presentation to put together given such a large amount of information. I tried to highlight the design, the engines, the commands, etc.. I relied on audience questions to act as tangents …

On his blog, Kaj Arnö has been writing about MySQL news, events, community and business developments for some time.

His most recent posts include (1)  a thank you note to David Axmark, one of the MySQL founders, for his 20-year contributions to MySQL and FOSS, and (2) an announcement regarding the move from MySQL contributor license agreement (MySQL CLA) to Sun Contributor Agreement (SCA), which is expected to be more contributor friendly.   

First, AddThis.com (where I was the director of IT) and Clearspring have merged! A side effect of that is that I’m now (happily, on purpose, by choice) a full-time consultant! I’ll have a web site up soonish. Until then, check back here for updates. If you’re a tech firm who needs help, and don’t mind remote workers, send mail to bkjones at Google’s mail service (.com).

Some folks thought I’d passed away due to the uncharacteristic lull in posting frequency on this blog. I’m very much alive — but working for a startup and maintaining a consulting business simultaneously is hard, especially when two large projects fall into your lap at the same time. So what have I been up to?

Well, as part of the now-public merger between the company I worked for and the new company, …

I volunteered to give a presentation on MySQL at the next NoVaLUG (http://www.novalug.com) meeting, Oct 4th. Topics to include: installation, configuration, administration, replication, backup/restore, architecture, monitoring and troubleshooting. I won’t be deep-diving on any particular topic (too much for the time slot) but, instead, focusing on the basics.

Should be a fun time.

Knut Anders Hatlen writes about memcached user-defined functions (UDF) for Java DB on OpenSolaris.

Knut has also mentioned the recent release of Apache Derby 10.4.2. A corresponding Java DB release should be available for download soon. (Usually this happens immediately but we're all at a developers' conference for the next couple of …

Although we had previously planned to make MySQL 5.1.26 RC into the GA or production release, we've decided to instead incorporate two more release candidates into the schedule. The goal is to make sure that MySQL 5.1 is absolutely rock solid, even if it takes a few more months to release it as GA. Given the additional two releases candidates, I expect MySQL 5.1 will GA in late November of this year.

First of all, there will be several dozen additional bug fixes included in a 5.1.28 release expected to be available mid-September. Many of these bug fixes were completed and queued up ready to go after the GA release as part of our monthly rapid update cycle. Since the GA obviously didn't happen, we're incorporating these into the RC immediately. The bug fixes generally fall into three areas:
-potential crash bugs
…

So Google Chrome – Google's attempt at an open source browser, came out yesterday and I took it out for a spin. At its heart is the Webkit engine (also open source) and Google Gears, powered by SQLite (can MySQL rival SQLite in applications like this?). Here are my thoughts.

• Fast – Chrome loads extremely fast, blazing even. Granted, my Firefox would probably load fast if I didn't have any addons as well. Sites like Amazon or …

Marten Mickos, who runs the MySQL business inside of Sun, will be featured next week on Sun's "Innovation Insider" interactive web radio show.  Marten will be talking about the upcoming Software Feedom Day (September 20), business & technology innovation, MySQL 5.1, Swedish drinking songs and more.  Best of all, Marten will be available to answer the questions you post to the show.  The show is live Thursday September 4 at 12:30 pm pacific time and will be available for replay.

I have challenged Marten that he should do the show in a penguin suit to show our commitment to all platforms, but since it's radio, it may be hard to tell... 

• Blog Talk Radio: …

I have a small EC2 instance running with a 25GB EBS volume attached. It has a database on it that I need to manipulate by doing things like dropping indexes and creating new ones. This is on rather large (multi-GB, millions of rows) tables. After running one DROP INDEX operation that ran all day without finishing, I killed it and tried to see what was going on. Here’s the results of the first 10 minutes of testing:

-bash-3.2# dd if=/dev/zero of=/vol/128.txt bs=128k count=1000
1000+0 records in
1000+0 records out
131072000 bytes (131 MB) copied, 0.818328 seconds, 160 MB/s

This looks great. I’d love to get 160MB/s all the time. But wait! There’s more!

-bash-3.2# dd if=/dev/zero of=/vol/128.txt bs=128k count=100000
dd: writing `/vol/128.txt': No space left on device
86729+0 records in
86728+0 records out
11367641088 bytes (11 GB) copied, 268.191 seconds, 42.4 MB/s

Ok, well… that’s completely miserable. Let’s try …