Now I figured out the reason for MySQL Server 5.1.24 crash when used with InnoDB plugin 1.0. As I had a older my.cnf in the path and it had innodb_flush_method=fdatasync as the default flush method. But from 5.1.24 onwards, fdatasync is not supported as the flush method (not sure why we have such a change in the final stage of RC code, but  …)

Even though I get an error in the mysqld.err log that InnoDB failed to register; but server starts and loads rest of InnoDB information schema plugins without the main InnoDB plugin.

InnoDB: Unrecognized value fdatasync for innodb_flush_method
080423 22:36:04 [ERROR] Plugin 'InnoDB' init function returned error.
080423 22:36:04 [ERROR] Plugin 'InnoDB' …

I’m still looking for new entries. I get quite a few suggestions, but not all of them make it into quiz questions. Do send in your suggestions!

Today’s quiz question, which subsequently became three, comes courtesy of Janek Bogucki.

Since questions 2 and 3 contain hints on the other questions, they are embedded within the answers to previous questions.

Question 1: What happens if you throw the following statement at your MySQL server?

CREATE TABLE log(
name CHAR(20) NOT NULL,
count INT UNSIGNED NOT NULL
)

(more…)

Hello my dear readers.

Today I have a question for all of you. What platforms (32bit or 64 bit) do you use for your servers with more than 4Gb RAM? I’m asking because recently we‘ve hit few really weird bugs in Linux kernels 2.6.18 to 2.6.22 and all those bugs were PAE-related. Now I’d really love to move all machines to 64-bit, but I’m in doubt because we don’t know too much about Rails stack (ruby, mongrel, haproxy) on 64-bit platforms (all our DB boxes are 64-bit of course).

So, please drop me a line if you have any experience (negative or positive) with Rails platform on 64-bit machines. I’d really appreciate your help.

Sometimes you have the task of storing multiple of boolean values (yes/now or something similar) in the table and if you get many columns and many rows you may want to store them as efficient way as possible.
For MyISAM tables you could use BIT(1) fields which get combined together for efficient storage:

PLAIN TEXT SQL:

1. CREATE TABLE `bbool` (
2.   `b1` bit(1) NOT NULL,
3.   `b2` bit(1) NOT NULL,
4.   `b3` bit(1) NOT NULL,
5.   `b4` bit(1) NOT NULL,
6.   `b5` bit(1) NOT NULL,
7.   `b6` bit(1) NOT NULL,
8.   `b7` bit(1) NOT NULL,
9.   `b8` bit(1) NOT NULL,
10.   `b9` bit(1) NOT NULL,
11.   `b10` bit(1) NOT NULL
12. ) ENGINE=MyISAM
13.  
14. mysql> SHOW TABLE STATUS LIKE 'bbool' \G
…

If you're following PlanetMySQL you've already seen Baron's post about MySQL Conference which many of us just have returned from.
It was great event as well as 5 conferences I've been before that, though however it more and more becomes MySQL marketing channel and business event rather than Users Conference as it originated. This Year even name was changed to be MySQL Conference and Expo though I have not noticed it until Baron pointed out

There is nothing wrong with MySQL Conference and Expo - there are product conferences out where for pretty much any mature product with large user base, however it may not put users interest first any more.
I've been talking to a a lot of people and many inside MySQL/Sun and out share the same opinion so we thought we …

There's been talk of a community conf, not to compete with but augmenting the Sun/MySQL one.
A Google Group was created to discuss the possility of such an event, its potential, dates/location, and get it going! It's a public group, please blog & tell others about it! Sheeri suggested OurSQL, like her podcast.
Here's the URL:

http://groups.google.com/group/oursql-conference

The group was set up by Peter and myself, after earlier discussion with Sheeri, and others - Baron is currently asleep but you may have seen his post earlier today where Marten also noted his support for such initiatives - initial group invites include MySQL community …

I am attending the Web2.0 Expo at San Francisco this week. Today was the first day of the conference and the crowds seemed to be larger than last year. The primary focus seems to be on social networking this year. 

I'll blog more about other aspects of the conference, but I wanted to focus this post on the twitter phenomenon. I'd heard of twitter of course, but I just could never figure out what it was all about. What was the big deal about telling the world what you were doing every second ? Who would even care ?

I attended a panel titled  "Short attention span theater: The birth of micro-blogging and micro-media". It was mediated by Gregarious Narain (he turned out not to be all that gregarious) and included Jeremiah Owyang (Forrester Research), Stowe Boyd (consultant) and …

I see this to often; Storing HTML in the database. Then UI wants to change the HTML, but the data grew to 100 GB, so the really only feasible way to change the HTML is via a post process after the database fetch. This post process produces a huge list of preg_replace statements to rebuild the HTML on display. This consumes a lot of memory over time and slows down the APP, plus its time consuming to debug.


Store URLS if the apps need to. Or better yet build the schema to store the bare minimum the app needs to generate the HTML.

Here is a compelling reason why not to store HTML:

The data needed to generate the HTML is 10 bytes, but the TEXT field consumes 1024 bytes, all of which is the same text.

Thus for an app that should cost very little to maintain now costs 10 times as much.

If your building a search engine strip out the HTML and store the text. If its a quick …

I will be speaking at Community One in San Francisco, the Sun event immediately before Java One.
The session is Creative Programming with MySQL, which is an euphemism for "hacking MySQL" :).
I will cover the basics of programming MySQL independently of your language of choice, using stored routines, storage engines, triggers, events, and MySQL Proxy.

Track: Databases
Room: Esplanade 307
Date: 2008-05-05
Start Time: 12:25

If you are in the area, come along!

We had over 400 participants in yesterday’s MySQL-Sun event in China! Plus another 30 or so in the press event, happening in parallel.

Beijing, if nobody noticed, is preparing for the Olympics. Here’s the so called Birds Nest, that we passed several times on the way to various meetings — including yesterday’s event.

After initial linguistic difficulties, Larry Stefonic (MySQL VP APAC) found our way to the event.

This was the first MySQL-Sun event with a banner across a street!

Everything takes place in Chinese here. About as much as it’s Japanese in Japan. In Europe, we seem to give way too much way for English.

And to accommodate to the local situation, I gave my presentation (on MySQL-Sun integration) in Chinese. It was about 8 minutes, and I was happy to be several times interrupted for applause. And I didn’t say anything …