Some words in advance...

Recently I wrote about multi-threading problems with java.util.Calendar and java.text.DateFormat. The last sentence was So maybe it is time to search your code for all static usages of the Calendar and various ...Format classes, before you start getting strange errors.

Searching code is not very practical, especially if you do it manually. Everyone knows you can look at code for hours, without seeing an problem - and as soon as it has reached production systems it starts breaking up in various ways :-)

Fortunately smart and reknown people have devised ways of making the computer look for bugs automatically. Amongst others, …

Wow!

[brian@zim memcache_engine]$ ~/tangent/bbench/network_run.sh
/home/brian/mysql-builds/example/bin/mysqlslap: Cannot run query INSERT INTO t1 VALUES (uuid(),1233983202,789373855,'jdtPbBILRQyiu7nZN3RdI96aQOP4Y0z7dlO4wbQF1OpvYdLnggGrqMP8mjCAjB9CwQHk1jruzhhXA2BibRZPqrPSQdX9gYDTyWDr5xdxWJSgDXEozg5hNW1pzYqgx3','9nQEfN38KZRh5hCCL3sRkFpm4pAuL7pWvFcQXgar52O3bdFwY7FHE53ImD47LtT81xaYT8Fb2YWd1lQZshqyelGOzCNCxsCyimMBmWep28IvlkSTIJRw4bDvnczlLB','bvpq6cCdH6db1NCTsWgKIdvXOb0OKDRn8HdEthjAnLdochAS3qgMJclk3d0FqR2ykY5dDof119pdqz6mie816ld9NdO55R4pr9J4pq5rrnSieQSK5SEB5rLKTlQQ4M') ERROR : Can't write; duplicate key in table 't1'

That should not be possible. I actually hit a duplicate key while using uuid() as the primary key.

Freaky weird...

So what does this mean?

It means I have found a bug... because that is a hell of a lot more likely...

Our next version of Connector/Net will include support for Compact Framework 2.0.  One thing that's been challenging is how to test our provider in this environment.  We have a NUnit test suite that we use with the normal provider but so far I haven't found any good way to run it under the compact framework.  I know about CFNUnitBridge but I needed something that could also work with compact framework 1.0.

So, I decided to write my own.  After two days of hacking I now have an application that does just what I want.  It loads my test suite and implements all the NUnit framework junk that I use.  I gave it a reasonable UI similar to what is seen in NUnit's GUI runner.  You can select a single test to run and have it run all the tests.  It also keeps track of exception messages and stack traces per test failure.  Here's a shot of …

There are various tools available for gathering and monitoring mysql performance data, but it’s not always clear what they mean, what is important, and what can be tuned. I’m not going to try to post a comprehensive mysql tuning manual here. This post is about taking a snapshot profile of a mysql instance that will allow you to define what type of instance you are dealing with, and give you some idea about whether the current configurations are stable or not.

I’ll be using a script that I’ve designed for daily reporting on the mysql instances that we monitor. This script will be available in a follow-up post, but for now, you can see the output of the report itself and a break-down of the more important sections.

To start with, let’s look at an example report:
Sample Report 1

Global engine stats: 13 [InnoDB] 183 …

I have just released CodeGen_MySQL_Plugin 0.1.0dev

This package has been around in PEAR CVS for quite a while, now it is finally seeing its first alpha release.

Starting with the upcoming 5.1 release MySQL will provide a general plugin interface within the MySQL server.
Up to MySQL 5.0 the only way the MySQL server could be extended without recompiling it was to add UDF modules that provide new user defined functions on the SQL level. The new generic plugin interface allows for different kinds of plugins to be implemented on top of it.

Currently the plugin interface supports the follwing kind of plugins:

• "daemon" plugins that only hook into server startup and shutdown
• fulltext parser plugins that change the way data is broken into words for fulltext indexes
• storage engine plugins
…

Tomorrow at 10.00 CET we will present the second webinar of the Online Solutions series.

We will talk about MySQL Replication and we will see some of the advanced techniques. We will set up basic, circular and multi-master replication on the fly, for those of you who are not yet familiar with this technology.

There are also hints, tips and tricks for advanced users and DBAs, with suggestions on hardware, storage engines and performance considerations, plus real examples from some big names - Yahoo, Flickr and Wikipedia to name few.

Thanks to everybody for the interest! This is the most successful set of webinars ever presented in Europe so far...

...and there's much more to see!

Stay tuned and see you tomorrow!

-ivan

P.S. The registration to the online webinar is  …

I’m visiting a Pentaho customer right now whose current “transaction” volume is 200 million rows per day.  Relatively speaking, this puts their planned warehouse in the top quintile of size.  They will face significant issues with load times, data storage, processing reliability, etc.  Kettle is the tool they selected and it is working really well.  Distributed record processing using Kettle and a FOSS database is a classic case study for Martens scale out manifesto. 

This organization doesn’t have unlimited budget.  Specifically, they don’t have a telecom type budget for their telecom like volume of data.  One of the issues that has come up with their implementation has been the tradeoff between space, and keeping the …

After two months of hard work we are proud to announce a new release of XAMPP for Windows and Linux. New in both releases of XAMPP are MySQL (5.0.37), PHP (4.4.6), phpMyAdmin (2.10.0.2), and OpenSSL (0.9.8e). The Windows version also contains up-to-date versions of: FileZilla FTP Server (0.9.23), ADOdb (4.94), and Zend Optimizer (3.2.4).

With XAMPP 1.6.1 we tried to make the Windows version ready for Vista. The beta tests were very successful and most people reported a very smooth XAMPP under Vista but there were also people still having problems. Please get in touch with me if you also encounter problems on Vista. Currently please avoid installing XAMPP into the "Program files" folder.

Get the downloads and more details on the platform specific XAMPP project page.

After some long months of intensive bug fixing, it's time to pack up the stuff and head off to the MySQL Conference & Expo. Since this is actually my first MySQL (User's) Conference, it's bound to be interesting.

We've got a full schedule here, so it will definitely not be boring.

Monday, April 23, 8:30am - 5:00pm, Ballroom D (with lunch 12:00am to 1:30pm). Lars, JDD and I am going to hold a replication tutorial for a full day where we'll go over some basics on how to set up replication to work properly, but also delve into some advanced stuff like row-based replication and cluster replication to …

I've made a lot of additions and updates to the "MySQL Storage Engine for Amazon AWS S3". Available, as always, via hg.