The latest from the MySQL community

MySQL Replication is asynchronous which causes problems if you would like to use MySQL Slave as it can contain stale data. It is true delay is often insignificant but in times of heavy load or in case you was running some heavy queries on the master which not take time to replicate to the slave replication lag can be significant. Also even very small lag can cause the problems - for example you've posted comment on the blog and on next page reload you do not see it as it was read from the slave millisecond later.... this is something you would not like to happen.

I'll list some techniques here which I found to be helpful for offloading load to the slave without causing application to be have crazy. The same approach can be used in Master-Master replication in Active-Passive mode, just think about passive node as a slave.

Query type based distribution Elect some queries as "time critical" and other queries as "non …

I thought “svn”, I typed “cvs”. Hrrm… sounds about right.

In other revision control news, using quilt to manage work-in-progress patches in conjunction with BK is proving really, really great. I feel like an idiot having lived this long and not worked this way.

I have a feeling that if git was being used I’d just do everything there as it’s so quick anyway. I haven’t used bzr on these sorts of size of repos yet, but it should be good too.

I was feeling pretty ill on Monday but I managed to recover enough to present today's webinar on developing applications for MySQL with Visual Studio.  We had a terrific turnout of +150 people and I've been told the presentation came off pretty well.  As a reminder, if you attended the webinar and have any question that you were not able to ask during the session, please email me directly and I'll get you an answer.

Even more exciting is the community feedback.  I received an email just a couple of hours ago from Jeffrey McManus who blogs about MySQL and .NET (among other things).  He wrote up a nice little article on installing MySql.Data into the GAC.  You can read it here.  Thanks Jeffrey, and keep them coming!

One of the main features that are unique to MySQL is that of pluggable storage engines. The most common ones are MYISAM for speed, InnoDB for transactions as well as ARCHIVE, CVS etc that can help with different problems. There are a few newer engines that people may not know about including Falcon (still alpha), PBXT and the SolidDB storage engine (by Solid Information Technology (www.solidtech.com).

Well, the SolidDB storage engine is one that I have been looking at recently as it supposedly scales very well due to multithreaded implementation and architectural design. I wanted to check the benchmarks and went to the website to find that the only binaries were for Linux and MS Windows. They did offer source however and I tried to compile MySQL with SolidDB storage engine support for Mac OS X (PPC) platform.

During the last days and weeks new releases of PHP (4.4.5 and 5.2.1), a new version of MySQL (5.0.33), and a new Apache (2.2.4) saw the light of the day. We're currently working on the new XAMPP version and invite you to take a closer look at the beta versions of the next XAMPP release:

http://www.apachefriends.org/en/xampp-beta.html

XAMPP BETA versions are always for testing purposes only. There will be no upgrade packages from and to beta versions. To all testers: Many thanks in advance!!

One of the strengths of mondrian's design is that you don't need to do any processing to populate special data structures before you start running OLAP queries. More than a few people have observed that this makes mondrian an excellent choice for 'real-time OLAP' -- running multi-dimensional queries on a database which is constantly changing.

The problem is that mondrian's cache gets in the way. Usually the cache is a great help, because it ensures that mondrian only goes to the DBMS once for a given piece of data, but the cache becomes out of date if the underlying database is changing.

This is solved with a new set of APIs for cache control in mondrian-2.3. Before I explain the API, let's understand how mondrian caches data.

How mondrian's cache works

Mondrian's cache ensures that once a multidimensional cell -- say the Unit Sales of Beer in Texas in Q1, 1997 -- has been retrieved from …

I'm starting to get into Django more and more, forgetting PHP. And some nice stuff is coming up.

Yesterday there was a post about a Django Cheat Sheet published by folks at Mercurytide. Still work in progress, but all tools are welcome for a 'starting' project.

And then there is the Django Book. It's getting quite heavy already in pages and you can leave comments to make it even better!
Of course, there are the usual PostgreSQL posts.. Well, they are funny. Like the one on Chapter 2 suggesting to indeed sort the database engines alphabetically because they should be equally good, but keep PostgreSQL first in the list.

Other comments suggest the MySQL python module MySQLdb doesn't work with Python …

I'm starting to get into Django more and more, forgetting PHP. And some nice stuff is coming up.

Yesterday there was a post about a Django Cheat Sheet published by folks at Mercurytide. Still work in progress, but all tools are welcome for a 'starting' project.

And then there is the Django Book. It's getting quite heavy already in pages and you can leave comments to make it even better!
Of course, there are the usual PostgreSQL posts.. Well, they are funny. Like the one on Chapter 2 suggesting to indeed sort the database engines alphabetically because they should be equally good, but keep PostgreSQL first in the list.

Other comments suggest the MySQL python module MySQLdb doesn't work with Python …

Inserting bullets into slides where previously there were none. Thanks OOo, reformating a number of slides was exactly what I was missing in my life.

Oh, and waiting an entire minute to save my presentation is also a great use of time. Funnily enough, my laptop disk (although slow) is faster than 1.3MB/minute.

An addition to The Long Tail of “The Long Tail” related blogs

The Long Tail effect of open source has been discussed in several contexts. Some of the interpretations are likely very different from what Chris Anderson intended, but more and more niche needs of a relatively small set of people (which don’t have economies to justify product development by proprietary software companies) are being met by open source software. Witness more than 140,000 projects registered on SourceForge.

Whenever I install Red Hat Linux I am amused by some of the choices available for the language of the operating system - what is different when running a Red Hat box with English(Singapore) vs. English(India)!? It is also heartening to see support for regional languages making computers accessible to even remote villages (which don’t provide economic motivation to proprietary OS providers).

The long tail effect of open source …