My second webinar (hey it's an officially recognized word now!) on memcached, Memcached for MySQL: Advanced Use Cases, is now available on-demand from MySQL website.

Also see:

• Slides for Memcached for MySQL: Advanced Use Cases
  

After stepping off of the GROUP_CONCAT() solution for calculating quantiles I figured it would be nice to find a better way to calculate the median too.
Solution
I previously wrote on how to calculate the median using GROUP_CONCAT(), but I think that this is a better way:

SELECT     AVG(length) AS median                 -- take the average of left and right median
,          MIN(length) AS left_median            -- 
,          MAX(length) AS right_median           --
,          @l          AS left_median_position   --
,          @r          AS right_median_position  --
FROM (
     SELECT     @n, length                       -- @n is just here to …

In http://www.mysqlperformanceblog.com/2008/07/01/should-we-proclaim-mysql-community-edition-dead/, Peter Zaitsev wonders if MySQL’s community edition is dead.

The title of Peter’s inquiry is somewhat misleading, as the database itself works fine. He clarifies a bit with, “there suppose to be 2 yearly binary releases (which are overdue) and 4 predictable yearly source releases, which we have not seen either.” I thought it was clear that “2 per year” doesn’t mean “one every six months”. It’s been eight months, sure. And I don’t actually believe that MySQL is going to have one source release per month until November, to make up for the lack of source releases. However, it’s certainly possible, if not probable.

The fact remains, however, that if you’re just looking for stable, recent, …

We did it. Designing Scalable Architectures with MySQL Proxy was delivered successfully, with over 150 attendees.
There is a large number of questions that were asked during the session, and you can find them in MySQL Proxy FAQ.
The slides, with the highly entertaining images used by John Loehrer to illustrate his point are also online
Finally, John posted his Connection pooler Lua script in the Forge.
Thanks to John Loehrer for his lively presentation, to Jimmy Guerrero and Rich Taylor for organizing the event, to Jan Kneschke, for answering questions online …

I keep talking about Flexviews, but I figured I'd step back and explain exactly what it does and how it can help you maintain aggregate tables cheaply. Read that again. It really is important. If you have a BI or DW running MySQL then you probably spend a lot of your time creating aggregate tables with cron jobs or some other ETL tool.

These aggregate generating queries might take many hours to run, and running multiple aggregations concurrently likely severely impacts performance. The more data you have the longer the aggregations take to run. If you are attempting to answer real-time business questions this presents a big challenge. Flexviews to the rescue. It gets rid of those cron jobs and custom aggregation scripts and replaces them with an API for creating materialized views (a fancy name for those aggregate tables). It supports two kinds of views: COMPLETE and INCREMENTAL refresh.

A COMPLETE materialized …

For those who don’t know the Obfuscator is for reporting bugs and support requests where the schema,data and queries are not allowed to be disclosed.

At the moment it requires PHP5+ and MySQL5+, the only requirement at the moment is the mysqli extension. It’s being written so that a simple command line interface will be added later as well as a way of interfacing with it directly in PHP. Because of the pluggable style infrastructure the possibilities are left wide open.

Features:

• Multiple Query Obfuscation Multiple queries in a single obfuscation
  procedure, so that tables are obfuscated consistently over a few related
  queries.
• Query Reformating the tokeniser will be able to pretty print queries no
  mater how ugly your query is.
• Pluggable Schema Obfuscation Obfuscation of schema will be …

In addition to having the Malaysia University Days, there’s something brewing in Singapore too.

First up, there is the Singapore MySQL Meetup Group, having a meeting in July, at a new location (Sun Solutions Centre, Central Mall). Confirm your attendance for a meetup at 7pm on Monday, July 14 2008.

And the other reason to be in Singapore, is the Sun Developer Days 2008 Singapore, happening on Tuesday, July 15, 2008. This is an all-day long event, held at the Hilton Hotel - register …

As of July 1 all Canadian MySQLers are employees of Sun Microsystems. I was expecting that we would be the rear guard, I was going to greet the great day singing “a broken man on an Edmonton pier / the last of Monty’s engineers” (with thanks to the writer of “Barrett’s privateers”), or perhaps “And I, the last, go forth companionless … Among new men, strange faces, other minds.” (with thanks to Mr Tennyson). But as things turned out, the Ukrainians and the French were delayed. So Trudy Pelzer and I were the last Canadian engineers to come on board, but not quite last of all.

And it’s been wonderful. A free lunch, a tour of Sun’s Edmonton office, a SafeWord security doohickey, a carrying case, and an alternative address = peter.gulutzan@sun.com. More seriously, I’ve …

I didn't have a chance yet to write about this due to some recent travel, but better late than never. About 10 days ago, Nokia acquired the remaining 52% of Symbian that they didn't already own for a cool $410 million. Nokia also announced that they would open source all of the Symbian code. This follows on Nokia's earlier acquisition this year of Trolltech, the open source GUI toolkit developer, for $153 million. For those not familiar with it, Symbian is a platform created jointly between Nokia, Ericsson, Motorola and Psion ten years ago. (Symbian evolved from the EPOC platform... READ MORE