Reading Sheeri's MySQL 5.1 vs. MySQL 5.5: Floats, Doubles, and Scientific Notation, I was baffled at this change of floating point number notation.

However, I was also concerned about the final action taken: using "--ignore-columns" to avoid comparing the FLOAT/DOUBLE types.

The --float-precision option for pt-table-checksum currently only uses ROUND() so as to disregard minor rounding issues. But it can very easily extend to handle the difference in floating point notation. Consider again the problem:

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FOSDEM is a free event that offers open source communities a place to meet, 
share ideas and collaborate.
It is renowned for being highly developer-oriented 
and brings together 5000+ geeks from all over the world.

 
This year again, be sure that FOSDEM will be the place to be in February!

Do you have any doubts? Really ? Dude, repeat after me :

Free event

During a week-end

Beer

5000+ open source geeks

Beer

MySQL and Friends devroom

NoSQL devroom

No registration needed (open source man!)

Ok, that sounds good?

Well, here are the informations to attend this terrific event :

• How to register? : Are you kidding me?
• When : 2 & 3 February 2013 (Hurry up guys!)
• Where : Brussels (beers!!!)

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common_schema 1.3 is released and is available for download. New and noteworthy in this version:

• Parameterized split(): take further control over huge transactions by breaking them down into smaller chunks, now manually tunable if needed
• duplicate_grantee(): copy+paste existing accounts along with their full set of privileges
• similar_grants: find which accounts share the

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Those who’ve been around the MySQL world are probably aware of the much-discussed topics of GPL licensing, dual licensing, and in particular, licensing of the client libraries (also called connectors or drivers) and the FOSS exception (http://www.mysql.com/about/legal/licensing/foss-exception/) to that licensing. This is newly relevant with the announcement of a permissively-licensed MySQL-compatible client library for MariaDB.

The difference is that this time there’s been some question about the provenance and history of the source code. Some people asked me about this. Some of them were aware of a relatively obscure detail: there’ve been permissively licensed MySQL client libraries for years, in the form of libdrizzle, a BSD-licensed library for the Drizzle fork of MySQL.

Here are some of the thoughts that seemed to be going through

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In my ongoing efforts to migrate my fun side projects and coding experiments from SVN to Git I’ve come across some of my favorite Python based apps – which are all available in their respective repos on BitBucket, as follows:

IRC Bot Commander

• What it does: it’s an IRC bot that takes commands and does your bidding on whichever remote server the bot is installed on.
• How it does it: the bot runs on whatever server you install it on, then it connects to the IRC server and channel you configured it to connect to and it waits for you to give it commands, then it execs the commands and returns the output to your IRC chat window.

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Unfortunately jQuery doesn’t come with default form validation to check for ip-addresses or subnet masking. So without a long winded explanation here’s the code. Just include this as a separate JS file like the rest of your page’s JS.

// 'ipv4': IPv4 Address Validator
$.validator.addMethod('ipv4', function(value) {
    var ipv4 = /^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$/;    
    return value.match(ipv4);
}, 'Invalid IPv4 address');

// 'netmask': IPv4 Netmask Validator
$.validator.addMethod('netmask', function(value) {
    var mask = /^[1-2]{1}[2,4,5,9]{1}[0,2,4,5,8]{1}\.
[0-2]{1}[0,2,4,5,9]{1}[0,2,4,5,8]{1}\.
[0-2]{1}[0,2,4,5,9]{1}[0,2,4,5,8]{1}\.
[0-9]{1,3}$/;    
    return value.match(mask);
}, 'Invalid IPv4 netmask');

You can use it like this.

$("#myform_here").validate({
    rules:{
	ipaddress:{

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As a follow up to the previous post about logstash, here are a couple of related init scripts for anyone implementing the OpenSource Log Analytics setup that is explained over at divisionbyzero. These have been tested on CentOS 6.3 and are based on generic RC functions from Redhat so they will work with Redhat, CentOS, Fedora, Scientific Linux, etc.

• Init script for ElasticSearch: located in the repo by clicking here – servicewrapper required
• Init script

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The Winter season for conferences is catching up speed.

DOAG

As I write this the DOAG conference in Germany is happening. It is one of the biggest (or the biggest?) Oracle user group conferences outside of USA. Many of my European friends in the MySQL space are talking there. As you know I have been a big fan of Galera Cluster for MySQL for over a year now, but I was perhaps a bit of an early adopter. Lo-and-behold, I was surprised to see the DOAG related press-release from SkySQL puts the creators of Galera first in their headline: Codership, SkySQL und weitere Top-Experten rund um das Thema ‘MySQL Datenbanken” in Nürnberg

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common_schema 1.2 is released! This version comes shortly after 1.1, yet contains quite a few interesting goodies:

• Account blocking
• Security audit
• RANGE partition management
• Slave status
• Better blocking and idle transaction management
• QueryScript goodies:
  • echo, report
  • while-otherwise statement; foreach-otherwise statement
  • Better variable scope handling
  • Complete support for variable expansion
  • Transaction support within QueryScript
• More summary info and SQL statements in processlist-related views

A closer look at these follows:

Account blocking

A new view called

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Two cons against NoSQL data stores read like this: 1. It’s very hard to move data out from one NoSQL to some other system, even other NoSQL. There is a very hard lock in when it comes to NoSQL. If you ever have to move to another database, you have basically to re-implement a lot [...]

“For analytical things, eventual consistency is ok (as long as you can know after you have run them if they were consistent or not). For real world involving money or resources it’s not necessarily the case.” — Michael “Monty” Widenius. In a recent interview, I asked Justin Sheehy, Chief Technology Officer at Basho Technologies, maker [...]

“For analytical things, eventual consistency is ok (as long as you can know after you have run them if they were consistent or not). For real world involving money or resources it’s not necessarily the case.” — Michael “Monty” Widenius. In a recent interview, I asked Justin Sheehy, Chief Technology Officer at Basho Technologies, maker [...]

To our Partners, Employees, Customers, Friends, and Community:

It is my unfortunate duty to inform all of you that DynamoBI is ceasing commercial operations October 31, 2012; we are immensely grateful for all the support that you all have shown our company, in so many different ways, over the past 3 years and we hope to make this shutdown as painless as possible for all involved.  We know that we are not the only people who are invested in LucidDB, so we wanted to explain our rationale for shutting down along with the implications for the entire LucidDB community (not just our customers).

We started DynamoBI 3 years ago when we saw our most favorite open source project, LucidDB, finding limited prospects for adoption without a growth to full, commercial support which many (most!) companies need to be able to adopt open source software.  We had been

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After a long pause in the speaking game, I am back.

It's since April that I haven't been on stage, and it is now time to resume my public duties.

• I will speak at MySQL Connect in San Francisco, just at the start of Oracle Open World, with a talk on MySQL High Availability: Power and Usability. It is about the cool technology that is keeping me busy here at Continuent, which can make life really easy for DBAs. This talk will be a demo fest. If you are attending MySQL Connect, you should see it!
• A happy return for me. On October 27th I will talk about open source databases and the pleasures of command line operations at

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I'm very happy to announce the release of common_schema, version 1.1 (revision 300).

This version boasts with compelling new features: innovative QueryScript syntax, libraries, views which add to your skills as a DBA, making some maintenance and management tasks a breeze.

• QueryScript, split statement: automagically break long queries into smaller chunks, avoid long locks and reduce query/transaction overhead
• QueryScript, try-catch statement: just try { something; } catch { act_on_error; }.
• killall(): quickly kill connections based on grantee/user/host information.
• profiling/profiling_last: utility views to assist in query

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The term Open Source is not as old as you may think, and the concept actually predates the name. Initially the keyword was Free not Open, but Free is here in the sense of Freedom not in the sense "without cost", and this conflict in the English term "Free" was one of the big reasons that Free really wasn't a good word here. Which all in all doesn't mean that Free isn't still used to describe the Open Source movement, like in FSF (Free Software Foundation).

And Free as in Freedom, not Free as in "without cost", is an important distinction. What the deal was, in my interpretation at least but there are many different views here, was that the software should be available for use by anyone and for any purpose as long as they followed the rules. And the rules was there for a number of purposes, two important ones being:

• To ensure

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