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See part 1 for the rationale behind the code and part 2 to understand limitations faced by cursors in MySQL.

The code snippet below shows an example that performs an action with the cursor data as well as a good way to debug the stored procedure. This iteration also works around MySQL's cursor problem mentioned in part 2 by calling the dynamic cursor fix stored …

A week ago Baron wrote a blog post which can only be described as the final nail in the coffin for MMM. At MySQL AB we never used or recommended MMM as a High Availability solution. I never really asked about details about that, but surely one reason was that it is based on using the MySQL replication. At MySQL/Sun we recommended against asynchronous replication as a HA solution so that was the end of it as far as MMM was concerned. Instead we recommended DRBD, shared disk or MySQL Cluster based solutions. Of course, to replicate across continents (geographical redundancy) you will mostly just use asynchronous replication, also MySQL Cluster used the standard MySQL replication for that purpose.

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Installing Apache2 With PHP5 And MySQL Support On Ubuntu 11.04 (LAMP)

LAMP is short for Linux, Apache, MySQL, PHP. This tutorial shows how you can install an Apache2 webserver on an Ubuntu 11.04 server with PHP5 support (mod_php) and MySQL support.

Last week I was at LinuxTag in Berlin. It was a great event. This time it was my second year there. I really enjoyed the first year and so I did this time as well. I spoke to many people, learned new interesting stuff and my todo list got again somehow longer And I believe that I also showed some interesting stuff to the people at our booth. I was speaking about GNOME Shell to anybody who happened to be nearby and everybody liked it! Good work, GNOME guys!
I’m glad I was able to be there and I want to share few pictures from the event with you, so even if you couldn’t make it there, you’ll see at least a little bit of what we were doing. We had a lot of fun

[Show as slideshow]

…

I have one free ticket to give away to RailsConf next week in Baltimore! Post a comment to win, and if you aren’t the winner, I’ll give you a discount code for Percona Live as a consolation prize.

Here’s the catch: you have to find at least one thing wrong with the following typical logrotate configuration for MySQL. This should be easy even if you’re not a MySQL expert

# This logname can be set in /etc/my.cnf
# by setting the variable "err-log"
# in the [safe_mysqld] section as follows:
#
# [safe_mysqld]
# err-log=/var/lib/mysql/mysqld.log
#
# If the root user has a password you have to create a
# /root/.my.cnf configuration file with the following
# content:
#
# [mysqladmin]
# password = <secret>
# user= root
#
# where "<secret>" is the password.
#
# ATTENTION: This /root/.my.cnf should be readable ONLY …

Brendan Gregg has a very good ongoing series of blog posts about the importance of measuring latency at the layer that’s appropriate for the question you are trying to answer. If you’re wondering whether I/O latency is a problem for MySQL, you need to measure I/O latency at the filesystem layer, not the disk layer. There are a lot of factors to consider. To quote from his latest post:

This isn’t really a problem with iostat(1M) – it’s a great tool for system administrators to understand the usage of their resources. But the applications are far, far away from the disks – and have a complex file system in-between. For application analysis, iostat(1M) may provide clues that disks could be causing issues, but you really want to measure at the file system level to directly associate latency with the application, and to be inclusive of other file system latency issues.

Someone should add Brendan’s feed to Planet MySQL. Here …

Brendan Gregg has a very good ongoing series of blog posts about the importance of measuring latency at the layer that’s appropriate for the question you are trying to answer. If you’re wondering whether I/O latency is a problem for MySQL, you need to measure I/O latency at the filesystem layer, not the disk layer. There are a lot of factors to consider. To quote from his latest post: > This isn’t really a problem with iostat(1M) – it’s a great tool for system administrators to understand the usage of their resources.

Henrik just wrote a good article on different ways of achieving high availability with MySQL. I was going to respond in the comments, but decided it is better not to post such a long comment there. One of the questions I think is useful to ask is what kind of high availability is desired. It is quite possible for a group of several people to stand in a hallway and talk about high availability, all of them apparently discussing the same thing but really talking about very different things.

The last article on this blog described our planned MySQL to MongoDB replication hackathon at the recent Open DB Camp in Sardinia.  Well, it worked, and the code is now checked into the Tungsten Replicator project.   This article describes exactly what we did to write the code and set up replication.  You can view it as a kind of cookbook both for implementing new database types in Tungsten as well as setting up replication to MongoDB.

The Team

MySQL to MongoDB replication was a group effort with three people:  Flavio Percoco, Stephane Giron, and me.  Flavio has worked on …

This is another article in a series of articles titled "A few notes ..." in which I will be posting some important information about locking concepts, different types of locks and what locks table engines support. Just like the previous article, the purpose of this article is to highlight important aspects that you should have in the back of your mind when developing applications.