Why demos?

For as long as I can remember in my public speaking activities, I have always planned my presentations with some sort of live demo in it. I am always surprised when a conference venue asks me to provide my slides in advance, to be loaded in an anonymous computer with no chance of demos. I always turn down such offers, as I always want to provide a demo.

There have been times when technical or time constraints prevented me from demoing something, and in these cases I felt that the presentation was lacking a vital part. But I always try. I have even given demos during lightning talks, and those were the ones that made me feel really good.

I have given hundreds of presentations, and hundreds of demos, and as in every human activity, I have made plenty of mistakes. I believe I have learned some valuable lesson from my mistakes, and this article is my attempt at sharing the joy with wannabe presenters and also with …

Reddit takes SQL injection very seriously.

How seriously?

Check their headers:

scabral-07890:~ scabral$ curl --head www.reddit.com
HTTP/1.1 200 OK
Content-Type: text/html; charset=UTF-8
Set-Cookie: reddit_first=%7B%22organic_pos%22%3A%201%2C%20%22firsttime%22%3A%20%22first%22%7D; Domain=reddit.com; expires=Thu, 31 Dec 2037 23:59:59 GMT; Path=/
Server: '; DROP TABLE servertypes; --
Date: Sat, 12 May 2012 13:54:20 GMT
Connection: keep-alive

scabral-07890:~ scabral$

A colleague at PICC showed me this when he learned of my talk on MySQL security!

Taxonomy of Database Tools

In the MySQL ecosphere there is an ecosystem of tools.  Like real-world ecosystems, the “creatures” in the MySQL tools ecosystem can be classified and organized by a taxonomy.  There are already multiple taxonomies of software bugs (e.g. A Taxonomy of Bugs), but as far as I know this is the first Taxonomy of Database Tools.  A taxonomy of database tools serves useful purposes, as discussed in the previously linked page.  For me, the most useful purpose is the high-level ecosystem view which I use to compare MySQL tools to  …

MySQL is one of the most, if not the most, popular relational databases chosen by internet based startups in the last decade. Although it is a very robust platform and offers many of the necessary features to support the database needs of today’s internet giants, it also suffers from some security issues that must be addressed prior to production use.

This article will discuss the necessary steps to secure a basic MySQL installation and additionally cover more advanced topics for general database security as would be applied to general production environments.

Functionality

The following general statements apply to this security discussion:

•This is a discussion of MySQL as installed on Linux; Windows, OSX, Solaris, and BSD installations may differ and the differences are not covered here.

•MySQL will be handling generic web traffic as is commonly found on PHP, Python, Perl, and …

A special extended edition of Tech Messages for 2011-09-21 through 2012-05-11:

• Understanding Linux CPU Load - when should you be worried?
• Performance Testing - Load Balancer SSL Stress Testing
  This is a great simple test. Thanks, Corey!
• Mosh: the mobile shell
• Twitter open sources its MySQL secret sauce
• Lab Overview
  This guy is serious about his lab!

This week we present how to use pt-archiver and pt-find, two Percona Toolkit tools. We focus on the common usage of the tools and the gotchas we ran into using them.

News/Events/Feedback
Conferences:
MySQL Innovation Day Schedule Tuesday June 5th, Redwood Shores, CA. Register here (free). Content will be available via live stream, so save the date!

…

A big welcome to the Portuguese MySQL Community.  The MySQL team has recognized your support of MySQL, so we hope you can take advantage of the new  Portuguese MySQL Planet.  Wagner has started us off with his blogs so please feel free to submit your Portuguese Feeds.

Some of our users have encountered problems with establishing a connection over the tunnel.php script despite the fact that the tunnel.php script is installed correctly. The following error message occurs: ‘Can’t connect to MySQL server on ‘your.sitename.com’ (10061): Authentication failed.’ The problem appears to be with cached proxy servers and will be fixed in one [...]

With the release of MySQL Cluster 7.2.5 we've released a version of MySQL Cluster where each data node is capable of using up to 51 threads in total. This is a remarkable feat for a product that only a few years ago was purely single-threaded. This article tries to explain what it is in the MySQL Cluster architecture that makes it so scalable to new HW demands.

The MySQL Cluster architecture is based on a design that is used in the world's most sold telecom switch, the AXE switch. This switch is used in all mobile networks delivered by Ericsson. MySQL Cluster also originates from Ericsson. The architecture of the AXE switch was developed in reaction to an older switch that had quality issues since there were too many global variables and too little modularity. The architecture was inspired by how HW was designed. In HW design each module can only communicate with other HW modules using signals (mostly electrical). The idea of the AXE …

Just a note on a problem that some people may find useful and may work for you if you have the same issue.

A client had a problem this morning with queries being aborted with the error message:

 Got temporary error 4006 'Connect failure - out of connection objects (increase MaxNoOfConcurrentTransactions)' from NDBCLUSTER

Here you would think that increasing the number of MaxNoOfConcurrentTransactions would help, but the root cause is something else (the client is not even close of hitting the default MaxNoOfConcurrentTransactions)

It turned out that during the night a couple of updates to the schema had been made (ALTER TABLEs to convert a couple of TEXT to  VARCHAR, so that a particular index could be created).

Looking in the mysql error logs we had:

120511 10:47:05 [ERROR] /usr/local/mysql/bin/mysqld: Sort aborted: Got …