It's been a busy year for MySQL. Perhaps you've heard. Here are some recent improvements to the speed, scalability, and user-friendliness of the MySQL database and the InnoDB storage engine that we think deserve their own headlines. Now is a great time to beta test the 5.5 release and give feedback to the MySQL engineering team.

An increasing number of large MySQL applications, e.g. social networking and SaaS back-ends, use a distributed MySQL architecture. MySQL data is distributed logically or heuristically on multiple, and in some cases thousands of, real or virtual servers. Backing up such large and dynamic environments presents its own complexities.

In this blog, we will use the cluster terminology - but we do not imply that NDB Cluster storage engine is being used for MySQL. Most implementations use InnoDB for data and MyISAM for dictionary. Typical architecture for such applications uses Database Sharding - i.e. shared-nothing partitioning of data across similarly configured nodes.

In most sharded environments, high availability is built-in - i.e. the cluster can continue to answer the queries and commit the transactions of all users in face of a node failure. This is typically accomplished either by database level replication or …

Quick note to let our users know that there was an XML tag closure error on the “alert_22″ subroutine in the “bin/kontroll-reporter-cli.pl” script. This does not affect the webapp portion of Kontrollbase – only reports generated via the command line reporter script. It is not a fatal error but will cause the XML file to […]

I have a brief keynote at the MySQL conference tomorrow at 10am. I will talk about the use of MySQL at Facebook. I promise that the talk will include interesting details.

I also have a short presentation at Ignite MySQL on Wednesday at 7pm. There are many interesting sessions on the Ignite schedule. Bradley Kuszmaul from Tokutek will be there. Unfortunately they do not have a talk about TokuDB at the MySQL conference, so this is our chance to try and remember everything from that algorithms class we had so many years ago.

Two reminders for upcoming appearances: This Saturday I’ll be presenting a 24-hour art collaboration with Evan Roth at Seven on Seven at the New Museum. On Monday I’ll be in Durham, North Carolina to speak at Duke University. If you’re interested in the latter, leave a comment and I’ll make sure you get the details. We don’t have a ton of room but I’d like ma.tt readers to be able to attend. After that I’ll be in Houston briefly if anyone wants to do a meetup.

Other day we had a small discussion about data stores and hardware; and which one drives the other when it comes to data storage solution, rather it is a hard discussion as both on its own are bigger entities; and one can not easily conclude as it depends on use cases and actually speaking data [...]

Every dump file created using the mysqldump command includes a clause named DEFINER. This clause cannot be excluded from the dump as of now, and hence whenever you try to restore the dumps on a remote database server or database server you would get an error referring to DEFINERS.

That is because DEFINERS have the information of the user and his IP, who has created or executed the SP/View/function from his login, hence it is not necessary for the user to have access over all the database servers.

You can remove the DEFINERS from the mysqldump file manually, however you would not want to do it by looking for DEFINERS on each line and then removing it. You need some script or a command to do this task for you.

Follow the below steps to achieving a dump file without DEFINERS,

Firstly create a mysql dump file,

>mysqldump –u root –p mydatabase>mydatabase.sql

I just got word that a talk about iSCSI High Availability with Pacemaker and DRBD, which I submitted for LinuxTag 2010, has been accepted by the selection committee.

The presentation is entitled Storage Done Right: Building a Resilient, Distributed, Highly Available Open Source iSCSI SAN and I will talk in the Storage track, in English. Questions in German, of course, won’t be a problem.

As the conference organizers have asked speakers not to publicize the temporary schedule (for obvious reasons — hey it’s temporary), I can’t give the exact time and location yet. But if you want to hear about how you can replace your six-figure SAN with something much more open, much less locked-in and much less expensive, plan a trip to Berlin in early …

After spending the morning looking over photographs with the amazingly talented Julian Cash, I drove through the pouring rain from San Francisco to the SJC airport, to pick up Brian Aker. From there, to the convention center, where I linked up with Monty Taylor, Jay Pipes, Stewart Smith, and a number of other people involved in Drizzle and Memcached. And from there, we all headed over to Sarah Sproehnle's place for a potluck party.

So much of the history and development of technology is based on a foundation of personal relationships. The people working on stuff get to know each other, and form friendships outside of just the work, and they introduce each other to their other friends, and from that, connections and cross-fertilization of ideas happen.

This is especially true for open source software and all the aspects of internet technology. The real but mostly …

I had a QA boffin email me with a question around the validity of data for a specific row in a development slave. Heres how I checked for him.

I set the pager output to md5sum. Heres an example:

Slave:
mysql> pager md5sum -
PAGER set to 'md5sum -'
mysql> select * from Residential where PropertyNumber = 106360678\G
0b07947002b59de27b6979fdcb57905a -
1 row in set (0.00 sec)


Master:
mysql> pager md5sum -
PAGER set to 'md5sum -'
mysql> select * from Residential where PropertyNumber = 106360678\G
1c6ac79d3fb2fd994ceb97406e9f2b1a -
1 row in set (0.00 sec)


Now onto why the slave is out of sync....