One of the themes from News Foo that continues to resonate with me is the importance of data journalism. That skillset has received renewed attention this winter after Tim Berners-Lee called analyzing data the future of journalism.

When you look at data journalism and the big picture, as USA Today's Anthony DeBarros did at his blog in November, it's clear the recent suite of technologies is part of a continuum of technologically enhanced storytelling that traces back to computer-assisted reporting (CAR).

As DeBarros pointed out, the message of CAR …

An SQL error which was a pain to get to the root of:
ERROR 1444 (HY000): The prepared statement contains a stored routine call that refers to that same statement. It’s not allowed to execute a prepared statement in such a recursive manner

Whist coding mysql reverse reconciliation for Securich (the Security plugin for MySQL) I kept getting the above error! We all learn from experience and I’m definitely not going to forget about this one :).

Having stored routines calling other stored routines in a cascading fashion for four or five levels can get complicated and what I was lazy about came to bite me right back. I copy code from one proc to the other (code re-use) thus end up having same variable names in different procs and prepared statements in cascading stored routines is not a smart idea, hence the above error.

Solution:
Give prepared …

I had earlier written a post on tuning the MySQL server configuration which was more geared towards the MyISAM storage engine. While that is not because I didn't intend on ignoring InnoDB but because I had planned a whole post on tuning InnoDB related configuration. So this post is the post that I had planned, I have discussed the major configuration parameters in here that should help you out most of the times.

MySQL has a great facility called the slow query log.  It allows you to filter out the most expensive requests against your database.  You may not have enabled it, however, and perhaps don’t want to restart your database.  In cases like these, a quicker way to capture queries is through tcpdumps of the port MySQL runs on.

Maatkit’s mk-query-digest has a tcpdump mode which can magically analyze this traffic for you, and produce a spectacular report of your top resource intensive queries.  In this Database Journal article we give it a once over.

Database Journal – Troubleshooting MySQL with Maatkit & Tcpdumps

When you run MySQL on a large NUMA box it is possible to control the memory placement and the use of CPUs through the use of numactl. Most modern servers are NUMA boxes nowadays.

numactl works with a concept called NUMA nodes. One NUMA node contains CPUs and memory where all the CPUs can access the memory in this NUMA node at an equal delay. However to access memory in a different NUMA node will typically be slower and it can often be 50% or even 100% slower to access memory in a different NUMA node compared to the local NUMA node. One NUMA node is typically one chip with a memory bus shared by all CPU cores in the chip. There can be multiple chips in one socket.

With numactl the default option is to allocate memory from the NUMA node the CPU currently running on is connected to. There is also an option to interleave memory allocation on the different parts of the machine by using the interleave option.

…

A couple of weeks ago I mentioned in a post that Monty Program was working on a trademark policy for MariaDB, and we hoped to have something available for community review in early 2011.

Well, that draft is ready now. The draft is available in the MariaDB knowledgebase, and we are soliciting public feedback through January 2. During the first week of January any approved edits will be made to make a final version, and that final policy mirrored on mariadb.org and montyprogram.com.

Hopefully the intent of allowing the unhindered development of cool stuff related to MariaDB while protecting the value of the primary brand itself is made clear. Let us know what you think …

I just wanted to express my appreciation for the 5.5 release. I know a lot of great engineers, documentation writers, testers, packagers, product managers, and even non-technical people must have done far more work on this release than we can see externally to Oracle, and many of those people might not be named anywhere. I know who some of you are, but surely not all of you. And, thanks to those who began this effort years ago at MySQL and then at Sun, who may not be involved anymore. Thank you to all of you, whoever you are.

Related posts:

1. MySQL Enterprise/Community split could be renewed under Oracle
2. Oracle is improving MySQL
3. …

As you are probably aware, PHP 5.3.4 does not compile with MySQL 5.5 GA. The details can be seen in MySQL bug queue. Basically, the problem boils down to incorrect installation of MySQL headers. MySQL 5.5 build system does not install the headers under the include-prefix/mysql directly but instead installs under the include-prefix directory itself. So, when the PHP build system looks for the MySQL headers, it cannot find <mysql/psi/mysql_thread.h> and so forth.

What is the fix?

The MySQL dev team has committed patches to fix this issue in …

We are pleased to announce the availability of the 2.0.2 release of Calpont InfiniDB Community.  This is our second maintenance release for 2.0.

Please note that with this release we have provided the ability to allow read only access to InfiniDB tables.  With the upgrade, existing users will need the following access to the new infinidb_vtable schema:

MySQL 5.5 is the latest production-ready release of the most popular opensource database management system on the planet ie. MySQL.