Edwin DeSouza had been nagging me about various web pages on the subject of online backup; one, on the Microsoft Developer Network, claims that it's bad to optimize your backup strategy for backup speed.

That's an interesting issue, and one that we thought about early on. We decided that, in general, it is good to optimize your backup strategy for speed. One size doesn't fit all, of course, but:

• The basic issue is that a fast backup can bring a slow recovery in its wake. That's often the case, but not always.
• The impact of a slow recovery depends on how often you do it. Our attitude is that a recovery is a very rare occurrence. The fact that we've got by without an online backup at all for so long reinforces this viewpoint.
• Backups …

I’ve written a lot recently about MySQL index and table structure, primary keys, surrogate keys, and related optimizations. In this article I’ll explain how MySQL’s index structures enable an extremely important query optimization, and how that differs between storage engines. I’ll also show you how to know and predict when the optimization is triggered, how to design tables and queries so it’ll be used, and how to avoid defeating it with poor practices.

I have finally decided to start using an RSS reader. Recent changes in the MySQL forums' behavior, layout and features have made it hard for me to see what forums have new posts have been made— so I will give the reader a try for a while and see if I like it better. I have subscribed to most of the forums, not that I am knowledgeable in all areas, but I find it interesting to read posts on subjects outside of my direct bailiwick.

So far so good, though I notice the feeds for a couple of MySQL forums aren't working, Database Adminstration and .Net. None of the foreign language feeds are working either, but I expect that is because they are brand new and haven't been posted in yet. I like the format of my chosen RSS client, similar to that of an email program for example the one I am using to peruse the news groups. Ultimately it would be nice to have one client that …

If you're doing significant amount of writes to Innodb tables decent size of innodb_log_file_size is important for MySQL Performance. However setting it too large will increase recovery time, so in case of MySQL crash or power failure it may take long time before MySQL Server is operational again.

So how to find the optimal combination ?

First let me explain what happens on recovery and why large innodb_log_file_size slows down recovery. During startup after crash Innodb scans log files to find log records which only have been applied in memory and do not exist in tablespace. Log records for modifications which did not make it to the tablespace are then applied. This is called redo phase of recovery. It can take pretty long time and this time depends on number of variables - how large are rows ? (smaller log records mean more records for same sized logs), how random were data modifications …

You think I'm kidding? No way!

There is this web page (I blogged about it a few months ago) where you get an interface to BitKeeper to watch the development activities: http://mysql.bkbits.net:8080/mysql-5.1/index.html.

Just for fun I replaced 5.1 with 5.2 and - it worked. So I followed the instructions from the manual and only replaced 5.1 with 5.2 again. This way, I ended up with a MySQL 5.2.0-alpha installation:

Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3 to server version: 5.2.0-alpha

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql>

I doubt that there are many (if any at all) differences to the current 5.1 development …

I'd like to chime in with Brian and remind you that the Hamburg MySQL User Group meets tonight, too! I have invited Jan Kneschke to give a talk about "Deadly sins in MySQL" (courtesy of Arjen Lentz) and I will also talk a bit about what's cooking at MySQL since the last time we met (it's been three months!). Looking forward to meeting you tonight - we will again meet at 19:00 in the Chinese restaurant Ni-Hao in Hamburg, Wandsbek.

Last week I was notified that my article about how to install and configure MySQL and the MySQL Connector/J was published in the Java Starter Magazine, a special edition of the german Java Magazin. It covers the basic installation of MySQL and Connector/J on Windows and Linux and how to write a small example program to connect to to MySQL with Java using the Eclipse framework. They were kind enough to send me a number of copies that I plan to give away at tonight's Hamburg MySQL User Group Meeting.

For those that are using a Referential Integrity based Storage Engine in MySQL, the use of Foreign Keys can provide an extra level of data integrity within your application. There are of course caveats to this statement, such as correct design, proper transactional use etc, but that’s a topic for another time. The use of CASCADE has an effect on this.

So, just a quick refresher, using the MySQL Sakila Sample Database (if you don’t have it, get it. This can be a valuable tool in many other areas). Let’s first check out the Schema Diagram. We will …

I’ve yet to find any Java project that doesn’t have dependancies on some other Open Source external libraries. I’ve yet to find a Java project that manages these external dependencies appropiately for support and integration at an enterprise level.

As with most projects, understanding an applying sound principles that scale will help you at a later date, and generally the cost of implementation is minimual at the start, but of course becomes more expensive when it’s really needed. The classic case is Version Control. For over 10 years, even on small single developer projects, I’ve used Version Control, it should be taught at university as an introduction to good programming design, it would greatly benefit software development and maintenance.

Back onto the topic of hand. Let’s use a moderate Java Web Based application, and for the purposes of this discussion the following Open Source external libraries are incoporated. …

In my previous blog article, I mentioned the fact that Red Hat’s deputy general counsel, Mark Webbink, lobbied in the European Parliament on July 5, 2005 (the day before the EP’s decisive vote to reject the software patent bill) to keep the software patent directive alive.

I had not anticipated the kind of Internet debate that this statement would trigger, including some insulting emails that were sent to me, and least of all I would have expected Mark Webbink to call into question the “veracity of [my] statements”, which is what he did in the discussion below this LWN.net article. He knows exactly what he did.

The word “motivations” also appears in that posting. It’s really simple: on the occasion of a patent suit having been filed against Red Hat, I thought it …