Having been a free software user and supporter for many years, I am disheartened by some of the comments made in the MySQL/Oracle debate regarding the GNU Public License (GPL) and other licenses. There is much throwing around of misconceptions and untruths about licenses and their differences. In this blog, I shall take on some of the bigger misconceptions.

While Linux is indeed distributed under the GPL, as is MySQL, Linux has an exception that allows anyone to run any kind of applications (including closed source applications) on top of Linux.

Monty says: Help keep the Internet free

There is nothing in the GPL that forbids running closed source applications on top of GPL-licensed software. The only thing that GPL has in this regard is that if you make changes to GPL-licensed software and re-distribute it as a binary, then …

I have just released PBXT 1.0.10 RC4. The sources can be downloaded from primebase.org, or from Launchpad.

The major feature in this release is the implementation of the pbxt_flush_log_at_trx_commit system variable. Similar to the InnoDB equivalent, this variable allows you to determine the level of durability of transactions.

This is a trade-off: by decreasing durability, the speed of database update operations can be increased.

The default setting is 1, which means full durability: the transaction log is flushed on every transaction commit.

Setting the variable to 2 reduces durability, by just writing the log on transaction commit (no flush is done). In this case, transactions can only be lost if the entire server machine goes down (for example a power failure).
…

A new version of CMON - the monitor for MySQL Cluster - has been released. Many thanks to everyone who helped me with bug fixing and beta testing!

CMON monitors all events and information that you can get from MySQL Cluster.

Some of the things that CMON monitors:

• Cluster status (starting, started, stopped, recovering, degraded etc)
• Data node status (started, stopped, starting etc)
• Application (mysqld) node status (connected/disconnected)
• DataMemory/IndexMemory/Tablespace utilization
• Statistics from data nodes
  
• Statistics from mysql servers
• Replication (basic currenty) support -picks up if a mysql server is a slave and checks if is running or not
• Alarm generation

There are pre-built binaries for Linux 64-bit (I have not got …

The Planet MySQL has been abuzz with opinions for or against the acquisition of Sun (and in particular MySQL) by Oracle, but I do not have a strong opinion to chime in with in support of either groups. The reason is that I do not know anything about antitrust laws, which is the legal basis for the EC blocking or not blocking the deal; and also I do not know what the alternative is to Oracle buying the MySQL part of Sun.

However, that does not mean that I can not join in the speculations about Oracles reasons for wanting MySQL in the first place ;-)

I think it is basically a matter of obtaining control over MySQL.

The horror scenario for Oracle is that MySQL (or Postgress or another Free Software program) does to the proprietary databases what Linux has done to the proprietary Unixes. Which is essentially to kill them, slowly but surely. This is not an …

On the eve of 2010.. and your boss wants to stick to these MacOS X 10.5 machines, too stubborn or chicken to upgrade. Some developers still have their old PowerBook laptops and they need MySQL flying on PowerPC machines. To top it all, one guy said he wanted to have 32 and 64-bit in one bite. *Sigh* .. But there is an easy way out! A universal binary!

This post shows you a way to create MySQL universal binaries using MacOS X 10.6 so you can run them on MacOS X 10.5/10.6 whether it is PowerPC or Intel, or 32bit or 64bit.

However, if you need …

Dennis Wolf, former CFO of MySQL, is in the hospital undergoing treatment for neuromyelitis optica (NMO) also known as Devic's Disease.  This is a spinal cord inflammation with similarities to Multiple Sclerosis.  Dennis is a very special guy to get such a rare disease. He's also a tough son-of-a-gun, so I have no doubt that he will put this behind him with a full recovery just as he did 18 years ago.  But it will take some time, attention and help from many people. 

He has started  …

It’s New Year’s Eve, a date that should strike terror into the hearts of many, because tomorrow a bunch of their queries are going to fail. Queries to “find all birthdays in the next week” and similar are always a nightmare to write. If you want to see a bunch of examples, go look at the user-contributed comments on the MySQL date and time function reference. This post is about a slightly saner way to do that.

Playing chess within MySQL? Over the network? In the .. cloud? Yes!

This is a follow-up post of my 'A chessboard in MySQL' where we create and populate a chessboard. But pieces need to move, and a few wondered how. Easy!

As an example, white openes with 1.e4:

  mysql> BEGIN;
  mysql> UPDATE chessboard SET e='♙' WHERE x = 4;
  mysql> UPDATE chessboard SET e='' WHERE x = 2;
  mysql> COMMIT;

Pretty obvious. Now lets put it in a stored procedure (source included in post) so the next move is easier on the fingers and more fun to play. Lets do a 1...e5:

  mysql> CALL move_piece('e','7','e',5);

The result is the following:

mysql> SELECT * FROM …

Iostat is a very handy tool to help you investigating what kind of performance problems you have. Especially your databases can cause a lot of troubles to your I/O system and thus it would be very nice if every DBA has installed iostat on all of his MySQL database servers.

Unfortunately most of the Linux distributions do NOT install iostat by default. This causes often unfortunate situations when you are in a MySQL consulting engagement or have a MySQL support case and ask the customer for the output of iostat. In some cases they are not willing or allowed to install iostat on their production systems on the fly (even though I never have seen it causing troubles during or after the installation).

Further iostat is also not too easy to find because is is hidden in the sysstat package. But iostat can be easily post-installed as follows:

shell> sudo apt-get install sysstat
shell> yum …

Iostat is a very handy tool to help you investigating what kind of performance problems you have. Especially your databases can cause a lot of troubles to your I/O system and thus it would be very nice if every DBA has installed iostat on all of his MySQL database servers.

Unfortunately most of the Linux distributions do NOT install iostat by default. This causes often unfortunate situations when you are in a MySQL consulting engagement or have a MySQL support case and ask the customer for the output of iostat. In some cases they are not willing or allowed to install iostat on their production systems on the fly (even though I never have seen it causing troubles during or after the installation).

Further iostat is also not too easy to find because is is hidden in the sysstat package. But iostat can be easily post-installed as follows:

 shell> sudo apt-get install sysstat
 shell> yum install sysstat
 shell> rpm -i …