At present, you can’t use the MySQL Workbench migration tool to migrate MySQL 5.0 to MySQL 5.5, as documented in Bug 66861. The only documentation reference that I could find that references the mysql.proc table. Since the physical definition of the mysql.proc table changes across the MySQL 5.0, 5.1, and 5.6 releases, I modified my documentation Bug 66886 to suggest providing online documentation (as a feature request) for the mysql, information_schema, and performance_schema tables across all releases.

The actual definition of the mysql.proc table for MySQL 5.0.91 holds 16 columns not 20 columns as presently expected by the MySQL Workbench migration …

So, what impact does enabling the slow query log have on MySQL?

I decided to run some numbers. I’m using my laptop, as we all know the currently most-deployed database servers have mulitple cores, SSDs and many GB of RAM. For the curious: Intel(R) Core(TM) i7-2620M CPU @ 2.70GHz

The benchmark is going to be:
mysqlslap -u root test -S var/tmp/mysqld.1.sock -q 'select 1;' --number-of-queries=1000000 --concurrency=64 --create-schema=test

Which is pretty much “run a whole bunch of nothing, excluding all the overhead of storage engines, optimizer… and focus on logging”.

My first run was going to be with the slow query log on. I’ll start the server with mysql-test-run.pl as it’s just easy:
eatmydata ./mysql-test-run.pl --start-and-exit --mysqld=--slow-query-log --mysqld=--long-query-time=0

The results? It took 18 seconds.

How long without …

With Percona Live NYC right around the corner I decide some of attendees what did they like on the last year event and what they are looking forward to in 2012. Here are some responses I got. If you’ve attended in 2011 or planning to join us in 2012 please feel free to comment with your feedback!

Ori Herrnstadt, CTO, Akiban Technologies says:
“I truly appreciated the opportunity to present at Percona Live NY last year and can’t wait to show how Akiban has progressed since then. As the founder of a company that is eliminating data complexity while preserving SQL and embracing new development paradigms, Percona Live offers the right mix of savvy technologists.”

Ryan Lowe, Production Engineer at Square Inc. says:
“This will be the fifth …

We are pleased to announce that MySQL Enterprise Monitor 2.3.12 is now available for download on the My Oracle Support (MOS) web site. It will also be available via the Oracle Software Delivery Cloud in approximately 1-2 weeks. This is a maintenance release that contains several new features and fixes a number of bugs. You can find more information on the contents of this release in the changelog:

http://dev.mysql.com/doc/mysql-monitor/2.3/en/mem-news-2-3-12.html

You will find binaries for the new release on My Oracle Support:

https://support.oracle.com

Choose the "Patches & Updates" tab, and then use the "Product or Family (Advanced Search)" feature.

And from the Oracle Software Delivery Cloud (in about 1-2 …

There have been a number of excellent articles about the pros and cons of automatic database failover triggered by Baron's post on the GitHub database outage.  In the spirit of Peter Zaitsev's article "The Math of Automated Failover," it seems like a good time to point out that database failure is usually not the biggest source of downtime for websites or indeed applications in general.  The real culprit is maintenance.

Here is a simple table showing availability numbers out to 5 nines and what they mean in terms of monthly down-time.

Last week I posted a MySQL Connect Guide for Developers. This week I am focusing on DBAs. The conference is about 2/3 administration/maintenance talks and about 1/3 development, with some overlap of course. Gerry and I did a lot of recommendations in OurSQL Episode 104, but that was before the schedule itself was up, so now I can present a list of session-by-session talks for developers who are building their schedules.

So here’s a guide to MySQL Connect for administrators, with times. Note that these are handpicked from what I think administrators would be interested in. There are many more sessions than the ones listed here, so head on over to the Schedule Builder to build your own schedule:

…

Last week I posted a MySQL Connect Guide for Developers. This week I am focusing on DBAs. The conference is about 2/3 administration/maintenance talks and about 1/3 development, with some overlap of course. Gerry and I did a lot of recommendations in OurSQL Episode 104, but that was before the schedule itself was up, so now I can present a list of session-by-session talks for developers who are building their schedules.
So here’s a guide to MySQL Connect for administrators, with times. Note that these are handpicked from what I think administrators would be interested in. There are many more sessions than the ones listed here, so head on over to the Schedule Builder to build your own schedule:
…

In a previous post, I noted that the new new password verification plugin in MySQL 5.6 provides a basis for implementing a more comprehensive password policy.  Most notably, password policies include requirements around password strength, duration, and reuse.  While the password validation plugin focuses on password strength policy components, there are ways to roll your own processes in support of password expiration and reuse policy components.  Unlike the password verification plugin, the tools I will describe below don’t hook directly into account maintenance commands.

You can download the full .SQL file (in a .ZIP package) here, and I’ll walk through the various …

As part of a recent engagement, I described the relative products to manage a MySQL pair (i.e. an Active/Passive MySQL masters configuration). This included the steps to undertake a controlled failover for supporting software maintenance using manual procedures. The upcoming Effective MySQL: Replication Techniques in Depth book details each step and all conditions to review over a dozen pages. While the steps are straightforward and generally well known, scripting this for your environment takes a certain amount of work to ensure your information is correct, and application connectivity loss is kept to a minimum.

In Continuent Tungsten (which I have just been reviewing these past few weeks), I achieved the same result with a single command.

$ echo "switch" | /opt/continuent/tungsten/tungsten-manager/bin/cctrl

In addition to all the …

Just yesterday I wrote about math of automatic failover today I’ll share my thoughts about what makes MySQL failover different from many other components and why asynchronous nature of standard replication solution is causing problems with it.

Lets first think about properties of simple components we fail over – web servers, application servers etc. We can put these behind some simple load balancer which can provide both high availability and fault tolerance. Technology can be made very robust because any node can handle request at any time and they all work concurrently. This means I do not have to move traffic
between the nodes but just chose what nodes participate in traffic handling which can be done a lot more seamless. This also drastically reduces risk of exposure in case of problems with setup.
I’ve seen …