The latest from the MySQL community

Aka, colliding MD5, but in a very cool 12-way demonstration:
We have used a Sony Playstation 3 to correctly predict the outcome of the 2008 US presidential elections. In order not to influence the voters we keep our prediction secret, but commit to it by publishing its cryptographic hash on this website. The document with the correct prediction and matching hash will be revealed after the elections.Read all about it at http://www.win.tue.nl/hashclash/Nostradamus/

(yes I share my first name with one of the authors, but you'll notice that the last name, while similar, is not identical - it's really not me. I'm not that much of a maths or crypto whiz ;-)

You will need:

• CMake (at least 2.4.7)
• Bazaar (the newer the better - 1.6 was just released - at least use that)
• Gnu Bison
• Visual Studio (Express works, but I’m talking about 2005 here)
• … and all this installed on a Microsoft Windows machine.
• … and to hate yourself, you are going to be using Windows after all.

Then, get and build it:

1. Get the source:
   bzr branch lp:~mysql/mysql-server/mysql-5.1-telco-6.4-win
2. Run CMake. the CMake GUI can now be used to select compile options! You’ll have to set the path “where is the source code” to where you put the source code in step 1.
3. Hit “Configure” in …

Along with some others, I have arranged a conference for open-source database users and developers.

Key facts:

It is of, by and for the community (you). At this event, all open-source databases are created equal. We’ll learn together and grow together. It’s a combination conference and hackathon. It’s free. It is Friday night Nov 14, 18:00 through Sun the 16th [...]

I came across this behavior today while writing some additional comprehensive ALTER TABLE tests for use in the test suite that we run against the Kickfire database appliance to ensure quality.

mysql> CREATE TABLE `t1` (
-> `col1` tinyint(4) DEFAULT NULL,
-> `id` int(11) NOT NULL DEFAULT '0' COMMENT 'min=1,max=65535',
-> PRIMARY KEY (`id`)
-> ) ENGINE=MyISAM DEFAULT CHARSET=latin1;
Query OK, 0 rows affected (0.00 sec)

mysql> alter table t1 drop column id,
-> add column id int auto_increment primary key;
ERROR 1089 (HY000): Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys

This is a regression in 5.0 (and 5.1, I didn't try 6) that was reported almost one year ago. This alter table works just fine in 4.1 and there isn't any reason it …

After last week’s post on agents versus agentless monitoring systems, I got a lot of email. One, from a customer whose name I am not permitted to mention, sent me the following action shot (posted with permission):

Over half a gigabyte; more than twice what MySQL itself is using. So, that raises an interesting [...]

With most large sets of data, especially numerical data, statistical analysis plays a key role. You can't be bothered to look at every record yourself; that's what computers are for.One useful tool in any statistical analysis is the identification of outliers. Assuming you have a normally distributed set of data, outliers can help to identify user error in the data entry process, or genuine spikes in the data. Once found, these numbers can be set aside for closer analysis or eliminated to normalize the data set.There are many different methods for identifying outliers, with varying levels of rigor. Here I'll just demonstrate one of the simplest definitions: an outlier is any value greater than three standard deviations away from the mean. ...

Sun Microsystems founder and Chairman talks about open source and the unification of Unix READ MORE

Robin just wrote a new article, titled A Quick Look at MySQL 6.0’s New Backup, and I thought, that maybe you’d like to also see this in presentation/video format…

At OSCON, Giuseppe actually gave a quick talk at the Sun booth, about our online backup. He also showed how to use it. All examples there, were done with the test-db sample database.

(MySQL Online Backup in Practice, video if the above doesn’t appear)

We timed our Use Case Competition to coincide with summer holidays, and are now prolonging the duration of the Use Case Competition with one month, until 30 September 2008.

To recap, here’s the original posting (with an updated deadline):

With 5.1 having officially been in Release Candidate status since September 2007 and soon approaching GA status, the MySQL Community Team launches a competition for the users of new features of MySQL 5.1:

Submit your MySQL 5.1 Use Case Report to community(at)mysql.com by 30 September 2008 and have a chance of winning one of our prizes:

• 1st-3rd prize: A MySQL Conference & Expo 2009 Pass, …

This book is just "too" popular ;-) It took a bit of jiggling with Amazon's stock levels (they say in-stock but if you order some quantity it'll delay the shipping, then you can tweak down and find out ;-), as well as a deal with the friendly people at Australian book distributor Woodslane, but Open Query can now offer anyone who participates (either an open course or custom/in-house training) in one or more training days between now and the end of this year a copy of High Performance MySQL (2nd edition).

You can also see this as an offer that benefits you directly rather …