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Bad SQL or MySQL Bug?

One of my colleagues made a typo in a query today that led to me discovering this issue -- I think it's a bug, though it may just be how the language is defined. But certainly a subquery that cannot run should not act as if it returns TRUE.

mysql> ...

Measuring MySQL Server Performance Talk Slides

There's no video for Jacob Nikom's December 2007 Boston MySQL User Group meeting, but the slides for "Measuring MySQL Server Performance" can be downloaded (2.33 MB) at

And with that, this is (I believe) post #10,000 at Planet MySQL!

Simple MySQL Proxy Failover

mysql-proxy defaults to round-robin load balancing. There are fancy tricks around to get mysql-proxy to balance connections based on how many idle connections there are in a proxy-based connection pool.

But there is no code that I found that would simply load balance based on "always go to ...

Unintentional Googlewhack Leads to MySQL Bug Report

While doing a standard audit for a new client, I recommended a few changes to get better performance. Because I had several changes, I used the documentation at

and found that innodb_flush_log_at_trx_commit is a dynamic variable. I was surprised, because most operations dealing with file sizes and operations ...

Can’t Make the MySQL Conference? Join Me Live!

If you can't attend the MySQL Conference, you can still virtually attend

Simply visit

2-3 pm PDT on Tuesday, April 15th for the "Best Practices for Database Administrators" session,


11:55 am -12:40 pm PDT on Thursday, April 17th for the "Database Security Using White-Hat Google Hacking" session.

You need nothing but your web browser; ...

Cluster Talk at March 2008 Boston User Group -- Slides and Video Are Up!

Well, nobody from Sun showed up in person, but we got a great rendition of "Where were you when you heard THE NEWS that Sun bought MySQL?" from Mark Rubin, the MySQL Sales Engineer for the New England area, and from Giuseppe Maxia, who revealed something very interesting and riveting.

From there, Giuseppe gave a short talk on what it's like to work at MySQL, and then we moved on to the topic of the user group meeting, "What is MySQL Cluster Good For?"

The slides for the talk are downloadable in PDF Format 61kB and Flash (SWF) format, 31kB

Pop Quiz: MySQL Cluster

If you have a 12-server MySQL Cluster with:
1 Management Node
3 SQL Nodes
2 Data Node Groups, 4 Data Nodes per group
And each machine is configured to allocate 1G of memory for its function, how much data (data + indexes) can you store in total in your cluster?
You can guess, but you get bonus points if you [...]

Automating To Save Time

This is the first place I am announcing this: The Pythian Group has made me a Team Lead. I am extremely honored and somewhat humbled by this, and I am determined to do a good job. I started officially on Monday, March 3rd, and my first week went pretty well.
On [...]

Why is Database Security So Hard?

I was recently asked a question by someone who had attended my Shmoocon talk entitled “Why are Databases So Hard to Secure?”. PDF slides are available (1.34 Mb). I was going to put this into a more formal structure, but the conversational nature works really well. I would love to see comments [...]

Hacking Open Source

Open Source means that the source code is open. There are many inferences that can be made from this, and many stereotypes that can be applied, but in the end, all it means is that you can read the source code as well as use the binaries.
I am not a developer. I fully [...]