MySQL has today refined its licensing scheme from “GPLv2 or later” to “GPLv2 only“, in order to make it an option, not an obligation for the company to move to GPLv3.

Specifically, this means that copyright notice in the MySQL source code files will change from referring to “either version 2 of the License, or (at your option) any later version” to “version 2” only, in the MySQL 5.0 and MySQL 5.1 code bases.

Six years ago in the summer of 2000, when MySQL AB licensed its software under the GPL, our founders David Axmark and Michael Widenius made this choice because the GPL was a license followed and respected by everyone. We have kept to it, because the GPL is the most palatable license, and poses the least friction for our user base.

MySQL has been part of the GPLv3 Committee …

To get the status of the replication slave, it is possible to check the Last_Error and Last_Errno fields from SHOW SLAVE STATUS. Unfortunately, they only give information about the status of the SQL thread (and not always that either). If the I/O thread fails, for example, because the server configuration is not correctly set up, or if the connection to the master is lost due to a network outage, it is necessary to dig through the error log to find out the reason. This might be possible, although annoying, for a DBA to do since he has access to the files on the machine where the server is running, but when using automatic recovery applications that watch the status of the replication, this is not practical. It is also easier to see the status of the server through a normal client connection, …

Everyone has heard of being slashdotted or maybe dugg. But have you ever been Yahoo!ed?

Phones started beeping, mayhem ensued. The first thing we looked at was the database. Is some MyISAM table locked? Is there a hung log processor running? The database was busy, but it looked odd. The web servers were going nuts.

As we soon discoverd, we (dealnews.com) were mentioned in an article on Yahoo!. At 5Pm Eastern, that article made it to be the featured article on the Yahoo! front page. It was there for an hour. We went from our already high Christmas traffic of about 80 req/s for pages and 200 req/s for images to a 130 req/s for pages and 500 req/s for images. We survived with a little tinkering. We have been working on a …

Today, I encountered a very weird problem.

Consider the following similar queries (one run with LIMIT clause and the other without it). The result set has been truncated for convenience.

mysql> SELECT 'photo_Q'  AS db, year_of_account_created,month_of_account_created, year_of_date_uploaded, month_of_date_uploaded, COUNT(distinct user_name) FROM photo_Q1.photo GROUP BY year_of_account_created, month_of_account_created ;
+---------+-------------------------+--------------------------+-----------------------+------------------------+---------------------------+
| db      | year_of_account_created | month_of_account_created | year_of_date_uploaded | month_of_date_uploaded | COUNT(distinct user_name) |
+---------+-------------------------+--------------------------+-----------------------+------------------------+---------------------------+
| photo_Q |                    NULL |                     NULL …

Matt Asay tagged me with a blog meme (sounds worse than it is) to write 5 things that most people probably don't know about me.  Let me apologize in advance for such a self-centered posting; I swear I'm just following orders!  Here are few little known facts, though people who read this blog regularly may know a couple of these already. 

1. I'm a marathon runner
   Running a marathon is harder than almost anything else you can do. Harder than working in a startup, harder than writing humor, harder than marriage.  But it's also a very rewarding experience.  I learned more in running my first marathon than almost anything else in life.  I've run 10 marathons in ten years as well as …

We just published a technical document about what to consider for backup and recovery of the remote MySQL server, for example, when your online forums and wiki are located at managed hosting service provider.

For any database backup the primary considerations are the consistency of the backup and impact on users and applications. A backup of the remote MySQL, however, has extra challenges related to:

• network usage
• security, and
• flexibility of recoverability of MySQL data to a different host.

We discuss the trade-offs to consider, and describe how to use Zmanda Recovery Manager (ZRM) for several common scenarios. For example, we provide HOWTO for a use case when you want to ensure security of backup data on the wire and at rest.

I'll echo what Kris Buytaert said about the MySQL Symposium in Amsterdam in March. It is going to be a great few days filled with a lot of detail about MySQL.

Among others, I'm looking forward to Jim Starkey's talk about Falcon Internals. Also looking forward to hanging out with other MySQLers, and Planet MySQLers.

Hope to see you there.

Some time ago, our GUI tools development team started a contest to shake out the bugs in the MySQL GUI applications, especially the MySQL Administrator and the MySQL Migration Toolkit.

The contest ran for about 3 months and resulted in more than 170 bug reports, of which the team fixed all the significant ones (over 120) by now. This is quite impressive, especially considering the relatively small size of the GUI development team. I am very happy to see that the quality of these tools has been improved, they are quite useful, especially for users not keen on using the command line.

The new MySQL Administrator 1.2.8 and MySQL Migration Toolkit 1.1.8 have now been declared production …

Some time ago, our GUI tools development team started a contest to shake out the bugs in the MySQL GUI applications, especially the MySQL Administrator and the MySQL Migration Toolkit.

The contest ran for about 3 months and resulted in more than 170 bug reports, of which the team fixed all the significant ones (over 120) by now. This is quite impressive, especially considering the relatively small size of the GUI development team. I am very happy to see that the quality of these tools has been improved, they are quite useful, especially for users not keen on using the command line.

The new MySQL Administrator 1.2.8 and MySQL Migration Toolkit 1.1.8 have now been declared production …

MySQL provides its replication for High Availability (HA) and for read Scale-out. Generally it is known that in a MySQL replication you can only replicate from one Master to many slaves. In this Whitepaper it is shown how a set-up can look like to replciate from two masters to one slave. Caution: Use these informations with care!!!