This is a HOWTO about installing MariaDB Galera Cluster on Debian/Ubuntu.
It is because a lot of people had problems installing MariaDB Galera Cluster.
In the end elenst from #maria on freenode forced me to write a Howto :)
You will find out, installing MariaDB Galera Cluster is in fact quite easy and some kind of boring in the end.
This Howto is written (tested) on Debian 7.1 (Wheezy) and Ubuntu 12.04 (Precise).

What we need

In our setup we assume 3 nodes (node01, node02, node03) with one interface.
We assume following IP addresses: 172.16.8.5, 172.16.8.6 and 172.16.8.4. We need three packages installed on all nodes:

• rsync
• galera
• mariadb-galera-server

As Galera does not ship with the distribution repositories, go for the …

In many parts of the MySQL world, whether you have users, developers or administrators of MySQL, the season holidays are for family, relax, prayers, travel, or they are simply a moment where you can enjoy what you like or care most about.

For me, this time is dedicated to my family, but also to deeper thoughts around the strategies to adopt in short and long term. My work nowadays, as the work of many others, is ruled by quick decisions, by the "time to market” - whatever “market" means in a specific context. Decisions must be made in meetings that are time-boxed in one hour or even less. In the end, you accumulate so much work and high priority tasks that you do not have enough time to prepare the topics adequately.

I thought I could summarise my thoughts for the past year and for the near future, from a technical and from a business perspective.

A transient 2013To me, 2013 was a transient …

Table structures are stored in .frm files and in the InnoDB Data Dictionary. Sometimes, usually in data recovery issues, we need to recover those structures to be able to find the lost data or just to recreate the tables.

There are different ways to do it and we’ve already written about it in this blog. For example, we can use the data recovery tools to recover table structures from InnoDB Dictionary or from the .frm files using a MySQL Server. This blog post will be an update of that last one. I will show you how to easily recover the structure from a .frm file and in some cases even …

Chinese and Japanese and Korean (CJK) text usually has no spaces between words. Conventional full-text search does its tokenizing by looking for spaces. Therefore conventional full-text search will fail for CJK.

One workaround is bigrams. Suppose the text is

册免从冘

There should be three index keys, one for each two-character sequence:

册免, 免从, and 从冘.

Now, in a search like

SELECT * FROM t WHERE MATCH(text_column) AGAINST ('免从');

a bigram-supporting full-text index will have a chance. It's wasteful and there will be false hits whenever the bigram isn't really a "word", but the folks in CJK-land have found that bigrams (or the three-character counterpart, trigrams) actually work.

One way to get bigrams for MySQL or MariaDB is to get mroonga.

Why care about Yet Another Storage Engine)?

Back in 2008 a project named Senna attracted the …

I’ve worked with every release of Microsoft Excel, and I know it takes effort to keep up to date with certain releases. Clearly, the Data Analysis eXpression (DAX) Language introduced in Excel 2010 went unnoticed by many, which was sad. DAX is truly a powerful extension to the analytical and modeling approaches in Microsoft Excel.

I’d like to recommend Microsoft Excel 2013 Building Data Models with PowerPivot to those who haven’t learned how to use DAX in Excel 2010, 2011, or 2013. DAX works with tables but if you don’t use tables, I guess you can skip DAX …

The year is almost at its end. Looking back at the past year I think it was a good year for MySQL. The 5.6 release was released in February and has been proven to be a very good release. There were many folks who reported bugs, which is good as this means they care about the product. But MySQL is not only a product, its a large ecosystem. One of the big players in the ecosystem is Oracle and this year they really participated in the MySQL community by having their engineers attend conferences which were not organized by Oracle (Like Percona Live and FOSDEM).
 
This year I couldn't attend the MySQL Connect and Percona Live conferences, but I hope to be able to attend in 2014 again. I did attend FOSDEM, which is a really nice (and different) conference.

For MariaDB it also was an interesting year as a number of  Linux distributions and customers switched from MySQL to MariaDB (and sometimes back again). I wonder …

Today new version of JSON UDF functions: 0.3.0 was released. This is major release which contains new functionality. You can download functions from the MySQL Labs website.

What was added?

Functions JSON_EXTRACT, JSON_CONTAINS_KEY, JSON_APPEND, JSON_REMOVE, JSON_REPLACE, JSON_SET now accept both string and integer arguments as array indexes. (Bug #70393/17491709)

Now syntax JSON_EXTRACT(doc, 'key', 1); is accepted.

New function JSON_SAFE_MERGE checks JSON documents for validity before merging them. In addition JSON_MERGE now merges valid documents, having array as root element. (Bug #70575/17583568)

JSON_VALID now accepts array as a root element of the JSON document (Bug #70567/17583282)

Also this release contains following bug fixes:

71050/17882710 …

Profiling mysqld on windows using visual studio 2012 profiler tool (vsperfcmd)

Recently, when I was doing performance assessment of one  innodb feature 
using sysbench standard tool then I observed performance drop in the feature.

I had some  hands on experience with  codeanalyst (AMD's tool) so I did sampling profiling. 
I attached profiler vsperf to mysqld when sysbench client was doing transaction with some 
concurrent threads and captured the data for 1 minute.
Just for information, there are 2 technique of profiling -1 sampling and instrumentation. 
For instrumentation, I had limitation because a)our  test  framework starts mysqld in instrumentation 
profiler needs to start mysqld  
b) in-between framework does shutdown  for some clean-up of data and 
c) instrumentation profiling requires debug build.

The codeanalyst does not provide very detailed data like 'vsperf' provides. 

Using visual studio IDE, we can profile (sampling or instrumentation). 
In my …

One of the most important and daily activity of DBA is taking backup and restore operations. Some times also required to create a new replicated server (Slave), which can be easily made possible with xtrabackp utility. The restore and backup is very fast as compared to traditional backup utility. The tool can be downloaded here.

Percona Xtrabackup is free, open source hot backup utility for MySQL and it's fork. It doesn't lock the database during the backup process.

Utility:
xtrabackup          -  a compiled C binary for only InnoDB/XtraDB data.
innobackupex    -  a perl script that provides functionality to backup whole MySQL instance with InnoDB, MyISAM and XtraDB tables.
…

It's again that time of the year. Analysts are spending oceans of words to predict the future, companies are making plans for the next year and people are resting and enjoying the break with their families. To me, this is the perfect time to reflect on my choices, the direction I'm headed to and consider if I still love what I do.

At the beginning of the year I decided to join MongoDB (formerly 10gen). The more I think about it, the more I realize I've been wrong. Yes, it's been the worst decision in my life not to join MongoDB when I was first offered the opportunity years ago. At that time an insightful friend asked me to consider the opportunity. At that time I didn't see what I see today.

I didn't see the …