Today I started my new job at PrimeBase Technologies. The company that has brought you the PBXT and Blob Streaming Pluggable Storage Engines for MySQL 5.1.

My move to Germany has gone mostly without incident and now I’m settling in to different weather, language and food, plus the change in time zones +6 hours.

A smaller company from my previous, but I’m part of a larger group then expected. One of 26 people in the office. It’s good to have a desk, a big monitor (and definitely not a German keyboard) and see and talk to people on various topics and interests in comparison to either past work at home by myself, or on a new customer site each week during my consulting days.

Preparations for the upcoming …

Continuing on from my lightning visits with Jan Kneschke and Michael Zinner, today I got to spend a day with Paul McCullagh at his home in Hamburg Germany.

Paul is the architect of the PBXT Pluggable Storage Engine for MySQL 5.1, and also the Blob Streaming Storage Engine. His work was acknowledged with the MySQL Community contributor for the year in 2007. The successful PrimeBase product for the publishing Industry in Europe and North America also now uses PBXT for underlying data storage which is great …

Top marks to Jay Pipes for getting the Forge 2.0 finally out after quite some time, as well as in the midst of the MySQL Conference he is organizing.

I am worried however about some of the content, as shown in the screenshot below, the opening page lists Worklog tasks/features for versions 6.x or 7.x , that’s ok, but features in 9.x. Where is the practicality of thinking more then 2 releases ahead, and just having a future bucket. Indeed, we have 5.1 and 6.0 already frozen and not releases, so 6.x is already 3 releases out.

Tonight we were told at the NY PHP Meeting MySQL 5.1 is not due to late Q2, so that’s at least June 2008.
The …

I am a very strong proponent of Open Source (excluding my Macbook). Joining MySQL Inc was a wonderful achievement, being part of the team behind the most popular open source database. Leaving MySQL was not an easy decision due to the people, but the Sun transition and requirements did help. However it is no surprise I am joining another open source company - Primebase Technologies in Hamburg, Germany. My association with the MySQL Community will only be strengthened with my full work and support behind the PBXT and Blob Streaming pluggable storage engines for MySQL.

It is actually poetic that I am joing Primebase for I have the auspicious recognition while an active part of the MySQL community of introducing Paul …

I have just released the first fully durable version of PBXT. Because of the amount of new code I have reverted PBXT to Alpha status. This version, 1.0-alpha, can be downloaded from: http://www.primebase.org/download.

Oh, which reminds me: PBXT now has a new home at http://www.primebase.org, so take a look around! I have actually found a bit of time to write some documentation. Right now the documentation describes building, installation, and the PBXT system parameters. Future additions will include information on performance tuning and a road map for PBXT development.

But there is more to the new home than just a new web-site. The PBXT project is now owned and funded by PrimeBase Technologies, an open source software development …

Yesterday I starting testing PBXT using the DBT2 benchmark. Following the implementation of durability and SELECT FOR UPDATE for the engine I was more interested in the benchmark as a test for stability and concurrency than performance. I was not disappointed...

Which bug first?

Well I immediately ran into 3 bugs. Isn't it funny how bugs often come in batches, which leaves you thinking: "Oh sh.. where do I start?". Here's my advice: start with the bug that is most likely to disappear if you fix the others!

A simple example, you have 2 bugs: an unexpected exception is occurring, and you're loosing memory. First look for the memory loss, because it may disappear when you fix the exception (because you may be loosing memory in the error handler).

Take things one problem at time:

Another thing: once you have decided for one of the bugs, stick with it (no matter how hard it gets) …

Until now PBXT has been ACId (with a lower-case d). This is soon to change as I have had some weeks to work on a fully durable version of the transactional engine (http://www.primebase.com/xt).

My first concern in making PBXT fully durable was to what extent I would have to abandon the original "write-once" design. While there are a number of ways to implement durability, the only method used by databases (as far as I know) is the write-ahead log.

The obvious advantage of this method is that all changes can be flushed at once. However, this requires that all data be written twice: once to the log and after that, to the database itself.

My solution to this problem is a compromise, but I think it is a good one. In a nutshell: short records are written twice, and long records are written once. When it comes to durability, this compromise, I …

This is quite a milestone for me! At last it possible to actually do some practical work with the BLOB streaming engine (MyBS)!

For this release I have completed changes to the MySQL Connector/J 5.0.7, to allow BLOB data to be transparently stored and retrieved from the MyBS BLOB repository. The new version of the driver is called MySQL Connector/J SE (streaming enabled).

Uploading a BLOB is as simple as using setBinaryStream() or setBlob() on INSERT or UPDATE. By using getBinaryStream() or getBlob() after a SELECT you get direct access to the data stream coming from the repository. More information and some examples are provided in the documentation at: http://www.blobstreaming.org/documentation.

To try this out you need to install the latest versions of PBXT and MyBS. Both are available from: …

With some effort just before my holiday, I have managed to complete the release of the next version of MyBS, the BLOB streaming engine for MySQL.

This version includes all the basic functionality required to stream BLOB data in and out of MySQL tables.

The main features are:

• Uploading of BLOB data directly into the database using HTTP PUT or GET methods.
  
• Downloaded of BLOB data directly from the database using HTTP GET.
  
• BLOB size may exceed 4GB - theoretical BLOB size limit of 256 Terabytes.
  
• BLOBs are stored in a repository which manages references from other storage engine tables.
  
• BLOBs are referenced by a URL.
  
• URLs referencing BLOBs in the repository have a unique access code, for security.
  
• The theoretical maximum repository size is 4 Zettabytes (2^72 bytes) per …

In the first two articles in this series, I discussed archiving basics, relationships and dependencies, and specific archiving techniques for online transaction processing (OLTP) database servers. This article covers how to move the data from the OLTP source to the archive destination, what the archive destination might look like, and how to un-archive data. If you can un-archive easily and reliably, a whole new world of possibilities opens up.