Innodb primary key is special in many senses and I was always wondering how well MySQL is integrated with Innodb to take advantage of these special features.

Lets see which things work and which things do not:

I used the following simple table for tests:

PLAIN TEXT SQL:

1. CREATE TABLE `innodb` (
2.   `id` int(10) UNSIGNED NOT NULL,
3.   `a` int(11) DEFAULT NULL,
4.   PRIMARY KEY  (`id`),
5.   KEY `a` (`a`)
6. ) ENGINE=InnoDB DEFAULT CHARSET=latin1;

"myisam" is same table created with MyISAM storage engine used to show difference:

MySQL Optimizer correctly knows Innodb tables is clustered by primary key in the sense it would not be faster to do external filesort than to do lookups in primary key order:

PLAIN TEXT SQL:

1. mysql> EXPLAIN SELECT * FROM …

I've written and spoke a lot about using short PRIMARY KEYs with Innodb tables due to the fact all other key will refer to the rows by primary key. I also recommended to use sequential primary keys so you do not end up having random primary key BTREE updates which can be very expensive.

Today I would like to share practical example when you may use long primary key with value distribution far from sequential.

For one of the projects I had the task to store meta data about thumbnails for images retrieved from various web sites in the Internet. Thumbnails themselves were stored on the disk of course but meta data such as original image sizes, file size as well as thumbnail location on the disk were stored in the database:

PLAIN TEXT SQL:

1. CREATE TABLE `imagecache` (
2.   `url` varchar(255) character SET latin1 NOT NULL DEFAULT '',
3.   `thumb_width` …

This morning is rich for troubles
Some PHP script was to act with MySQL database, but it failed with: “Warning: mysql_connect(): Client does not support authentication protocol requested by server; consider upgrading MySQL … Client does not support authentication protocol requested by server; consider upgrading MySQL client“.
I’ve digged a bit and solution was very simple -
SET PASSWORD FOR user@localhost = OLD_PASSWORD(?newpassword?);
This updates password to use old authentication protocol.

It now appears that our fearless leaders are pushing through legislation that will make it easier than ever to remove your freedom from you.  Mr. Bush is wanting the ability to jail anyone he wants for as long as we wants without charging them.  This is in addition to several other points in this new legislation that are all allegedly designed to help win the war on terror.  This is terrible legislation and nothing good can come from it.  However, my point is the hypocrisy of the left.  They will have no trouble declaring that everyone has a right to universal healthcare, a right to an education, and a right to a home.  We as American citizens have none of these rights.   While government run universal healthcare would be a deathblow to this country, privately run universal healthcare would be a welcome privilege.  So, too, is an education or a home.  …

SoonR is a hot new startup company that enables users of mobile devices (any mobile phone, smartphone or wireless PDA) to access all of the information they have on their PC.  By installing SoonR client software on your PC you enable access to your desktop files, contacts and even the Skype service from your phone.  You can access documents on your PC from your phone and forward them to others while away from your PC.  You can eliminate expensive long distance charges using Skype from your mobile phone.  How cool is that?  The basic SoonR service is free and they are also working on premium services that will provide additional levels of security and availability.

Not surprisingly, SoonR has been growing quickly.  Their initial prototype version was built using SQL Server running on Windows.  The developers had a lot of experience using Microsoft technology …

I'm not going to pretend that it was easy to nail this Q&A with the CEO and Co-founder of MuleSource. The company has been hiding in plain sight for about 2 months and my quest for an interview has been nothing short of Indiana Jones meets Get Smart.

Nonetheless, I persevered and bring to you a delightful Q&A with myself.

Q&A with Dave Rosenberg, CEO, MuleSource Inc.

Just what is Mule?
Mule is the leading open source ESB (enterprise service bus) and integration platform. Mule has been downloaded more than 200,000 times and is in production at more than 100 companies and governments worldwide.

The open source Mule project was founded in 2003 by Ross Mason, CTO of MuleSource …

The Lafarge group, a global leader in building materials, has selected the MySQL® database to operate the real-time management of the different sales and dispatch phases of its Aggregates & Concrete business. The system is already installed at over 100 quarries, with plans to service up to 250 production sites in Europe by the end of autumn 2006.

The Lists of MySQL Certified Candidates now also include the new Certifications for MySQL 5.0 - Certified MySQL 5.0 Developer and Certified MySQL 5.0 DBA:

http://www.mysql.com/training/certification/candidates.php

Also new is that you can now find some statistic figures. You can see how many have passed each individual Certification and on the detail page you also find how many people have passed this particular Certification in each specified country. So you can for example easily say: I'm one of eight Certified MySQL 5.0 DBAs in Germany.

Looks like we have a new version. From the announcement:

MySQL Connector/Net 5.0.1 Beta has been released. MySQL Connector/Net is an all-managed ADO.Net provider for MySQL. While this release is suitable for any version of MySQL, it is strongly encouraged that this release not be used on any production data. This release is feature complete with the exception of DTC support in System.Transactions.

It is now available in source and binary form from the Connector/Net download pages at http://dev.mysql.com/downloads/connector/net/5.0.html and mirror sites (note that not all mirror sites may be up to date at this point of time - if you can’t find this version on some mirror, please try again later or choose another download site.)

The following major changes are listed:

• Support for ADO.Net 2.0 interfaces and subclasses …