Yes, I know. JavaOne is about Duke, the friendly mascot of Java technology. Created and maintained by James Gosling and all.

But MySQL also introduces Sakila to the JavaOne attendees. Sakila is also friendly, and the mascot of MySQL technology. The dolphin was chosen by MySQL founders Michael “Monty” Widenius and David Axmark, as was its name Sakila (which came from a naming contest in the early days).

Together with Giuseppe (in the picture above) and the rest of the MySQL Community Team, I will be handing out incarnations of Sakila (also seen above in the pic) at CommunityOne and JavaOne as follows:

• Monday 5 May 2008 09:30-10:45: CommunityOne General Session: Ian Murdock, Sun Microsystems; Panel: Matt Asay, Alfresco CNET, Mårten Mickos, MySQL, Jim Zemlin, Linux Foundation, Ted Leung, Python, Stormy Peters, …

At the 2008 MySQL Users Conference and Expo, Mårten Mickos delivered the "State of the Dolphin Keynote". See all the blog posts others have written about the tutorial from the Forge Wiki at http://forge.mysql.com/wiki/MySQLConf2008TuesdayNotes#State_of_MySQL.

At the 2008 MySQL Users Conference and Expo, Lars Thalmann and Mats Kindahl gave a tutorial on replication. Download the slides and see blog posts others have written about the tutorial from the Forge Wiki at http://forge.mysql.com/wiki/MySQLConf2008MondayNotes#MySQL_Replication_Tutorial.

If you'd like to download the WMV video file in parts, here's a link to:
Part 1, 175.27 Mb
and

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At the 2008 MySQL Users Conference and Expo, Brian Aker (MySQL) and Allan Kasindorf (SixApart) gave a presentation on Memcached and MySQL. Download the slides and see blog posts others have written about the tutorial from the Forge Wiki at http://forge.mysql.com/wiki/MySQLConf2008MondayNotes#Memcached_and_MySQL.

If you'd like to download the WMV video file in parts, here's a link to:
Part 1, 112.09 Mb

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In a little app where users can create tabs and portlets in those tabs I ran into some issues with my ordered list implementation. It turns out I just misplaced a filtering expression in the WHERE clause instead of the JOIN condition. The basic idea was that I wanted to add new portlets in the left hand column at the top. The positions from the portlets actually start at 0, but what I am doing is to insert them at 1 below the current minimum or -1 if the table is empty. Then in a second query I push everything up by one. Seemed like the most efficient way to deal with concurrency. I guess in theory I could even skip pushing things up by one, but oh well.

Here is the original query (note that I am using PDO which supports Oracle style named placeholders for all drivers including MySQL):

INSERT INTO user_tab_portlets (tab_id, portlet_id, pos, col, is_open, config)
            (SELECT :tab_id, :portlet_id, COALESCE(MIN(utp.pos)-1, …

…or I’m doing something stupid, in which case I hope someone would enlighten me.

We grab a number of data from two different MySQL servers, get them back as arrays ($ar1 and $ar2) and then we concatenate the two arrays. $ar1 consists of 30 to 200 elements, sometimes more. $ar2 typically contains 30 elements.

The PHP way of doing this is:

$ar1 = array_merge($ar1, $ar2);

and the home-grown version is

foreach($ar2 as $i) {

 $ar1[] = $i;
}

While I do realize that “the PHP way” involves creating a new copy of $ar1 along the way, my assumption before testing this was that, being an internal function with no further parsing or interpretation to be done, it would be much faster.

Doing some microtime() estimations while keeping $ar2 constant at 30 elements, I found:

• At 1-10 elements in $ar1, array_merge is about 33% faster.
• At 20-40 …

An excellent ending to a great educational day. The party was outstanding. I didn't realize I had so many dance moves left in me. Thanks to the people that showed me some cool dance moves that made me look good.In previous times, people discounted the telephone, automobile and Internet as being toys and play things for people with too much idle time. The same people that laugh at how short

I really enjoyed the Sun Employees Connect event. Sun executives such as Jonathan Schwartz, Martin Mickos, Rich Green, Don Grantham, John Fowler, Karie Willyerd, Hal Stern, Lin Lee shared ideas, perspective and direction for the organization. Sun's innovativeness and strategic directions make it a lot of fun to go to work everyday. I really felt a lot of the same closeness and willingness

I'm travelling to Melbourne in a few weeks, to teach another edition of some Open Query course days. Three days this time:

• Optimisation by Design
• Storage Engine Optimisation
• Replication Workshop

There are still some seats available; you can sign up for individual days, and there's very special pricing available for students! The Melbourne dates are 12-14 May (Monday-Wednesday). I'm doing on-site consulting later in the week.

Interesting Google tech talk: Supporting Scalable Online Statistical Processing.

Goes for an hour and has a slowish start but around the 10 minute mark the beef starts... basically, rather than doing complete aggregates, he uses statistical sampling to provide a reasonable estimate (unbiased guess) of the result.

This makes sense, statistically!
It might be possible to transplant his system into a MySQL storage engine, but it would need to be able to do in-engine joins, something that MySQL doesn't yet support.

(Thanks Ian for the link)