If you are reading this, it means that world moves on and somebody somewhere was wrong in predicting the end of it. The ageless Log Buffer Edition presents you yet again some cool blog posts just before the holiday season to top up your excitement. This Log Buffer #300 is as sweet as the holidays...

Just a quick note to say that the site has been updated to a new theme which is based on the super awesome Twitter Bootstrap UI framework. To make life easier, since this site is also using WordPress at the core, I’ve made use of the WordPress Bootstrap plugin which allows for very simple integration. However, that wasn’t enough because the Bootstrap plugin comes with rather basic and boring generic styles; so I added the plugin for Google Font support and then modified the CSS accordingly.

You will also notice that the site is undergoing some reorganization of categories and content tags. This should help clean up search results as well as general information sorting. I’ve removed the sidebar widget for category listings in favor …

The content here is not new. I have written about same before many years ago (I think in our old Blog system that is now offline for 4+ years).  But I feel like to restate my point of view after listening to the latest OurSQL Episode. I was a little excited if Sheeri and Gerry would express similar concerns in their podcast, but they did not.

This is my concern: You may build an application on top of a database schema using TRIGGERS. And it may work perfectly as long as the database is only accessed from the application. However sooner or later it will likely happen that some maintenance or other database manipulations is required that was not foreseen when the application was written, and thus the application cannot handle it and you will need to connect with another client. It may be a problem because once you start doing manipulations …

If you are using SElinux, you should know that it’s advised to disable it to avoid issue with PXC. Generally the communication between your nodes doesn’t work properly and a node having SElinux enabled won’t be able to join the cluster.

So when a node doesn’t join the cluster where it should, my first reflex is to have a look at audit.log. But recently I faced another problem: the node joined the cluster but SST failed (whatever which method was used, discarding skip).

I checked SElinux and it was of course disabled, then I add some debug information in the SST script but it seemed that the script was never launched. And this time the culprit is called : AppArmor !

Percona doesn’t provide any AppArmor profile for PXC, but it seems that on this server (Ubuntu TLS), a previous version of MySQL was installed and then removed but the AppArmor profile was still present.

So if you use apparmor (or if you …

We are doing a migration from Amazon RDS to EC2 with a customer. This, unfortunately, involves some downtime – if you are an RDS user, you probably know you can’t replicate an RDS instance to an external server (or even EC2). While it is annoying, this post isn’t going to be a rant on how RDS can make you feel locked in. Instead, I wanted to give you a quick tip.

So here’s the thing – you can’t stop replication on RDS read replica, because you don’t have (and won’t get) privileges to do that:

replica> STOP SLAVE;
ERROR 1045 (28000): Access denied for user 'usr'@'%' (using password: YES)

Normally, you don’t want to do that, however we wanted to run some pt-upgrade checks before we migrate and for that we needed the read replica to stop replicating. Here’s one way to do it:

WARNING! …

I recently worked on a Rails 3.2 project that used the sweet PLupload JavaScript/Flash upload tool to upload files to the web app. To make it easier for users to upload large and/or remote files to the app, we also wanted to let them upload via SFTP. The catch was, our users didn't have SFTP accounts on our server and we didn't want to get into the business of creating and managing SFTP accounts. Enter: ProFTPD and virtual users.

ProFTPD's virtual users concept allows you to point ProFTPD at a SQL database for your user and group authentication. This means SFTP logins don't need actual system logins (although you can mix and match if you want). Naturally, this is perfect for dynamically creating and destroying SFTP accounts. …

Offers user a easy way to keep data write protected on RW and allows server to run even on RO media.

She hired the 400+ original MySQLers … and sets out to hire the SkySQLers of tomorrow! Boel Larsen blogs about open positions & life at SkySQL - and wants you to join the fun!

Those of you who know me also know that I spent over six years working for MySQL HR (for another couple of years I stayed on with Sun).  I joined as employee thirty-something, so running HR meant that I was more or less involved with hiring all of the 400 or so employees who joined after me. I knew pretty much everyone by name.

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Sergey Glukhov (Gluh) recently wrote an interesting blog about InnoDB secondary key improvements in MySQL 5.6. His blog isn't aggregated to planet.mysql.com but certainly deserves some attention. 
Here it is: InnoDB, extended secondary keys.

First, a thank you to everyone who attended the webinar Today, I appreciate your time and nice comments. As promised, here are answers to questions that couldn’t be answered during the talk:

Q: How do you install the tools?

The manual has full details, but it’s important to know that the latest release for every tool is also available for direct download in a url like this: http://www.percona.com/get/<tool-name>. I use this a lot when I just need a specific tool and I’m working on a server without the toolkit installed.

Q: How to make the tools connect to MySQL

The slides are now available here, and slide 7 provides a basic introduction to Data Source Names, with more details available …