A bunch of (hopefully) self-explanatory slides about new subquery optimizations in MySQL 6.0 is available here (UPDATE: here's a working link). The slides are from this MySQL University session, so there was an audio stream but there were some difficulties with it and it is not available now.

If you miss the audio, the next opportunity to hear about this topic is the New Subquery Optimizations in MySQL 6.0 …

It’s just three weeks now before the 2008 MySQL Conference. Good to see my mug shot on the front page (see screen shot below).

I will still be presenting my session Top 20 DB Design Tips Every Architect Needs to Know, however as a departing MySQL Employee I’ve had to give up the chance to present the “MySQL for Oracle DBA’s Bootcamp” tutorial, content that I developed for MySQL specifically and have already presented three one day seminars in New York, San Francisco and Washington DC.
Update March 26 2008. I should clarify that I notified MySQL as part of my exit items that I would not be able to present the Tutorial. I would very much like to, and being the author of the content I am well qualified, however as this was developed for MySQL and …

I was interested to note that as of this morning, attendee registration numbers for the MySQL User Conference (which O'Reilly co-produces with MySQL) are up 32% over the same period last year. This seems to be a good sign that the community is energized by MySQL's acquisition by Sun.

The conference takes place April 14-17 at the Santa Clara Convention Center. Among other things, we'll be hearing from Jonathan Schwartz, the CEO of Sun, about Sun's open source strategy (presumably including their plans for MySQL), as well as a deep technical program with tracks including Storage Engine Development …

Recently, I noticed a post on Planet MySQL expressing distaste for surrogate keys. Ever since reading it the topic has been bugging me so I thought I would finally break out a defense for surrogate keys.

Really, it comes down to the right tool for the right job. Like The Force, they can be used for both good and evil. The fact is that a surrogate key can be wildly useful and efficient if used in the right context. For instance, this blog uses surrogate keys here and there. I'll be honest, in some cases it may help and hinder. For instance, to maintain uniqueness, my BlogPosts table has an auto incremented primary key. To me, this makes sense. Yes, I …

Twice a year, Sun invites their Sun Fellows, Sun Distinguished Engineers and many Principal Engineers, Sales Engineers and Consultants to an offsite meeting, usually in California and this time in the Chaminade in Santa Cruz. For the first time, we now had MySQLers present — and over 20 of us.

The purpose of the meeting is to share new trends, new technologies, and new ideas across Sun’s wide spectrum spanning everything from the bare metal of the Niagara system through other aspects of system all the way to software.

I was fortunate enough to be given the opportunity to describe MySQL the Product, MySQL the Business and MySQL the Culture, in a long 90 minute day session in front of all the audience. Our Product, Business and Culture were described by a six-headed panel, with Jim Starkey, Jan Kneschke, Michael “Monty” Widenius, Mikael Ronström, Igor Babaev and Serg …

A lot of people seem to spend a lot of effort comparing storage engine in MySQL - chiefly focusing on the difference between MyISAM and InnoDB.

People normally compare:

Feature sets:InnoDB: better durability, transactions, MVCC, foreign key constraints, row-level locking. MyISAM: fulltext, spatial indexes, table-level locking
Run-time performance: (see your favourite benchmark)

But few compare actual storage space usage. As this is very important to our application, I decided to run some tests.

I'm testing here with a realistic-sized table for our application (we partition data into daily partitions and spread them across many servers anyway, so this is just a small piece). We currently use MyISAM, and this is a typical table with approximately 4 million rows.

I can't dump the schema or content of this table here for confidentiality reasons, but it has:

On Thursday, the day before the long weekend (Friday being Good Friday, following week Monday being Easter Monday), the Melbourne MySQL Meetup group met, for an event that was not our usual meetup, but that of a Meetup Mashup.

Held at RMIT, I spoke about the recent purchase, what changes, what doesn’t, and how we’re 100% committed to making the same great product even better. After that, Gary Pendergast, spoke about how the support is run, and how nothing changes there, except its becoming beefier! We also had a Sun Campus Ambassador, Zhiqi Tao speak about the campus ambassador program, and how he evangelises Sun technologies at universities (his particular one, being Melbourne University). There is also apparently an RMIT ambassador, who missed the meeting.

After the talk, a pocket of us headed to dinner at the Oxford Scholar. There was much beer to …

Few days ago I wrote about testing writing to many files and seeing how this affects sequential read performance. I was very interested to see how it shows itself with real tables so I've got the script and ran tests for MyISAM and Innodb tables on ext3 filesystem. Here is what I found:

The fragmentation we speak in this article is filesystem fragmentation or internal table fragmentation which affects performance of full table scan. Not all queries are going to be affected same way, for example point select reading single page should not be significantly affected - ie you may not be affected as bad as we show here.

Benchmarks were done using this …

It's Summer of Code time again -- a chance for students to do some real-world programming, contribute to an open source project, and earn $4500 over the summer. You have just one week, March 24 - 31, to submit an application.

Over on MySQL's Summer of Code Ideas page, I have listed some projects around MySQL Cluster and mod_ndb. They require some experience with C and C++. I'm hoping they will be great summer of code projects:

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• You get to work with Apache httpd -- the world's most popular web server since 1996, and a classic example of modular and portable software architecture.
  
  
• You get to work with cutting-edge technologies (like JSON, REST, MySQL Cluster, and Memcached) that will be more important a few years down the …

I have an issue I hope someone can help me with. I am generating RRDtool graphs (for Cacti monitoring templates for MySQL, which I'll release soon) that have up to 11 different metrics on them. With that many lines or areas on a graph, it becomes very hard to pick colors that are easy to see and easy to distinguish from each other. What's a good way to choose such colors?