A core economic principle is the Complementary Good . In short, when two or more things are used together, they are complementary. When the price of an item goes up, the usage of all of its complementary goods goes down. Similarly, if the price of an item goes down, the usage of all its complementary goods goes up. An example is the computer printer. Printers and ink are complementary goods. Proprietary ink products are extremely valuable—at one point ink delivered 60% of HP’s profits —so HP, understanding the principle of complementary goods, practically gives away printers because they make money on the ink. This is the classic razors and blades business model.

Businesses want to lower the cost of their products, while maintaining or improving their margins. …

Absolutely nothing?

5.4.0 was released with a change in the MySQL Binary distributions, delivering only 1 64bit Linux platform and two Sun Solaris platforms. This was officially announced on April 21 2009 however the 5.4.0 Release Notes state 05 April 2009. So it’s not a big deal, but consistency would be nice.

I’ve seen in a few posts 5.4.1, so I decided to try it out. Spending the time to read what’s changed in 2 months with the 5.4.1 Release Notes before I go downloading and installing, you read.

This release does not differ from 5.4.0 …

A core economic principle is the Complementary Good . In short, when two or more things are used together, they are complementary. When the price of an item goes up, the usage of all of its complementary goods goes down. Similarly, if the price of an item goes down, the usage of all its complementary goods goes up. An example is the computer printer. Printers and ink are complementary goods. Proprietary ink products are extremely valuable—at one point ink delivered 60% of HP’s profits —so HP, understanding the principle of complementary goods, practically gives away printers because they make money on the ink. This is the classic razors and blades business model.

Businesses want to lower the cost of their products, while maintaining or improving their margins. …

Look at MySQL bug reports of course? Well actually I’m writing multiple blog posts, and I was confirming additional reference sources and links when I came across MySQL Bug #29847 - Large CPU usage of InnoDB crash recovery with a big buf pool.

Taking the time to actually read the information exchange I stumble upon.

[8 Jun 23:29] liz drachnik

Hello Heikki - 

In order for us to continue the process of reviewing your contribution to MySQL - We need
you to review and sign the Sun|MySQL contributor agreement (the "SCA")

The process is explained here:
http://forge.mysql.com/wiki/Sun_Contributor_Agreement

Getting a signed/approved SCA on file will help us facilitate your contribution-- this
one, and others in the future.

Thank you ! 

Liz Drachnik  - Program Manager - MySQL

Oops. Well it made me laugh out loud for so many reasons. First your talking to the …

Recently with a client while running a number of disaster recovery tests I came across a nasty situation which was not part of the original plan and provided a far worse disaster situation then expected.

I should preface this condition with some of the environment conditions.

• MySQL 5.0 Enterprise 5.0.54
• RHEL 5 64bit
• Master and 2 Slaves
• MySQL Data and MySQL Binary Logs/MySQL Error Logs are on separate disk partitions

While running stress tests under high load, we tested the filling of partition containing the logs. This partition included the binary log and MySQL error log.

The observed output was.

• An error message was written to the MySQL error log. See below.
• Application throughput dropped, but did not stop.
• Binary logs stopped occuring.
• MySQL proactively stopped logging but continued to process …

Multi versioning concurrency control (MVCC) is a database design theory that enables relational databases to support concurrency, or more simply multiple user access to common data in your database.

In MySQL the InnoDB storage engine provides MVCC, row-level locking, full ACID compliance as well as other features.

In my understanding of database theory, access to modify independent sections of unique data (e.g. UPDATE) under MVCC should fully support concurrency. I have however experienced a level of exclusive locking under Innodb.

I wanted to clearly document this situation so I could then seek the advice of the guru’s in InnoDB Internals such as Mark Callaghan, Percona and the Innodb development team for example. I’m happy …

A couple of  weeks ago I got an unhappy email from my web hosting provider telling me I was in violation of their Terms of Service. Of course I called them immediately and was told that there was a “phishing page” hidden in one of my web directories. My blog had been hacked, so I immediately started doing some house cleaning.

After the initial once over and deletion of any suspicious files I went looking for advice on how to “harden my installation”. Here’s what I found:

• Wordpress.org Codex Hardening Wordpress - Lots of good information here on hardening Wordpress including a general overview of Wordpress security considerations.
• …

The MySQL KILL command as the name suggests kills queries that are running.

After identifying the Id using the SHOW PROCESSLIST command, the User of the connection/thread or a database user with SUPER privileges can execute KILL [id]; to remove the connection/thread.

However, there is an ability to kill just the query that is being executed rather the entire connection. The default when not specified is to kill the connection, however you can optional specify the CONNECTION or QUERY keywords.

For example, below is an interactive test.

Thread 1:

mysql> select sleep(10);

Thread 2:

mysql> show processlist;
+----+------+-----------+------+---------+------+-----------+------------------+
| Id | User | Host      | db   | Command | Time | State     | Info             | …

Today we increased price for the Amanda Enterprise Backup Server. The new price for our Standard subscription level is $500 per year. Our online store is a place to quickly checkout prices for all our products on a single page. This price increase was done in conjunction with release of Amanda Enterprise 3.0, which represents several man years of R&D on the backup server, including advanced media management such as D2D2T. Our subscription provides access to software and enterprise-class support.

Amanda Enterprise is used by businesses of all shapes and sizes. But a typical scenario is the following:

• Backup Server on Linux
• One tape library with one or two tape drives. Or VTL on a NAS device.
• A mix of Linux & Windows servers and …

There are many features that are similar in MySQL and Drizzle. There are also many that are not.

I’ve previously discussed topics like Datatypes and tables, SQL_MODE and SHOW.

A key difference in Drizzle is the definition of utf8 as 4 bytes, not 3 bytes as in MySQL. This combined with no other character sets leads to an impact on the length in keys supported in Innodb.

During a recent test with a client, I was unable to successfully migrated the schema and provide the same schema due to unique indexes defined for utf8 VARHAR(255) fields.

Here is the problem. …