MySQL Settings (also known as Server Variables) have interesting property. When you set variable in running server this change is not persisted in any way and server will be back to old value upon restart. MySQL also does not have option to re-read config file without restarting as some other software so approach to change config file and when instruct server to re-read it also does not work. This leads to runtime settings being different from settings set in config file, and unexpected change on restart a frequent problem.

pt-config-diff is the tool which can help with this problem a lot, being able to compare settings in my.cnf to those server is currently running with. The problem however this only works well if settings are set in my.cnf as if default option was used and we change it in run time we can’t detect such change easily …

Hello Folks,

I have never been consistent with blogging and most of the time
I create a blog hoping that I would  share my thoughts and plans
with everyone, but as It has to happen, I neglect it.

On this new year I made a resolution that I will work on this blog
(actually it was to create one) and maintain it throughout. This
blog will be the reflection of my ideas, and an attempt to get a feedback on
my work in MySQL replication, together with providing tips and tricks
on using MySQL in distributed environment.

So, last July I joined MySQL replication development team, straight out of
college and it is kind of a big thing for me. In past 7 odd months I have
worked with great people and learnt a lot of things and this has finally lead
to an idea of starting this blog, and posting my thoughts in my spare time.

This …

Links to performance numbers posted wrt various NoSQL solutions:

A top 20 global website announced they have migrated from MySQL to Redis. There will be a keynote and everything. It doesn't say how big the Redis Cluster is, but they serve 100M pages / day, and clock 300k Redis queries / second.
https://groups.google.com/forum/?fromgroups#!topic/redis-db/d4QcWV0p-YM

Btw, they mention that MySQL remains as the master data store from which the Redis indexes are generated.
(The reason I don't mention the name of this Redis user is simply I feat my mom is sometimes reading my blog...)

read more

New features in the 2.0 release:

• Galera 2.0
• MySQL-wsrep 5.5.20
• MySQL-wsrep 5.1.60

This is a major feature and bugfix release including support for Incremental State Transfer, foreign keys, and many critical bugfixes. For details follow download links.
Download

MySQL Cluster 7.2 is the best release to date, enabling projects and applications to benefit from web-scalability with carrier-grade availability and developer agility.


Oracle is delighted to announce the immediate availability of the production-ready, GA release of MySQL Cluster 7.2, available for download under the GPL, and as part of the commercial MySQL Cluster Carrier Grade Edition, including management tools, product certifications and 24x7 global support.



70x Higher JOIN Performance, NoSQL Key-Value API & Cross Data Center Sharding with Synchronous Replication
1 Billion Queries per Minute

MySQL Cluster delivered 1 …

Here are the lists of useful tools in comparing database snapshots, files and even folders.

1. dbForge Studio - It is a complete suite for all your needs in managing all your MySQL databases. This software can analyze your data and compare the differences and quickly create the diff statement ready to be executed. dbForge also offers Free edition the dbforge Studio for MySQL Express but of course with limited functionality

Features | Download

• Administration and Maintenance
• Backup
• Data Analysis
• Data Comparison
• Data Editor
• Database Explorer
• Debugger
• Exporting and Importing Data
• MySQL Connectivity
…

Database Best Practices for 2012: A Roadmap to Lower TCOIntended for IT Directors, C-level executives and their direct reports. If your organization suffers from unavailable, inaccurate or less-than-instantaneous data and struggle to strike a balance between affordable IT solutions and those that really deliver, join this webinar series to learn more about high availability paradigm shifts and business continuity best practices.

• Best Practice #1: Spend Less for High Availability.
  Watch it at your convenience. It is available now. (32 minutes)

 Tips, Tricks and Tools to Improve DBA Quality of Life: A Schooner Tech SeriesIntended for DBAs and Sys Admins responsible for managing, monitoring and maintaining data centers.

• Radically Simpler Database Admin: A Tour of the …

Making a compressed backup

mysqldump -u root -p database_name | bzip2 > output.sql.bz2
Restoring the compressed backup

shell> bunzip2 < output.sql.bz2 | mysql -u root -p
Copy database from one server to another

mysqldump db-name | ssh user@remote.box.com mysql -h remote.com db-name
OR

mysqldump -u username -p'password' db-name | ssh user@remote.com mysql -u username -p'password -h remote.com db-name
Copy only table foo to database bar

mysqldump db-name foo | ssh user@remote.box.com mysql bar
OR

mysqldump -u user -p'password' db-name foo | ssh user@remote.com mysql -u user -p'password' db-name foo

Vancouver, 2012-02-17 – One of my first tasks when I started at MySQL AB was to write an introduction letter for myself. At the time, we had a small team that was widely distributed across much of the world and the introduction letter (and yearly all-hands meetings) were important parts of helping our small team work effectively.

As I've worked with different organizations, I've tried to continue the habit – when I start somewhere new, I write a relatively personal introduction and encourage others to do the same.

Here's the letter that I wrote for the Magnolia team.
Thank you Boris! Greetings All,I'm quite happy and excited to be joining the Magnolia team: the product is solid, the people I've interacted with have been great and the company culture seems a good match for me. Also, it doesn't hurt that a dear friend (Sandro Groganz) speaks really highly of Magnolia as a whole.If you are really pressed …

Today I'm coming out of the closet. Since I'm a professional database expert I try to be like the mainstream and use the commercial MySQL forks (including MySQL itself). But I think those close to me have already known for some time that I like community based open source projects. I cannot deny it any longer, so let me just say it: I'm a Drizzle contributor and I'm very much engaged!

I've been eyeing the Drizzle project since it started in 2008. Already then there were dozens of MySQL hackers for which this project was a refuge they instantly flocked to. Finally a real open source project based on MySQL code that they could contribute to, and they did. It was like a breath of fresh air in a culture that previously had only accepted one kind of relationships: that between an employer and an employee. Drizzle was more liberal. It accepted also forms of engagement already common in most other open source projects that are based on …