Last Saturday I became father to a baby girl - in addition to our 2½year old son.
Those of you who are my former collagues from MySQL, you know about the generous Scandinavian 5 week vacations. (Which in MySQL were practiced globally.) I have decided that now is a good time for me to enjoy another Scandinavian perk: long paternity leave. I will be home with the rest of the family until approximately next February :-)
Mark’s done an excellent job again, getting VM’s of MariaDB 5.1.47 (release notes, changelog) out there for download. He’s also improved the bandwidth available at the box hosting these images. Get it for Ubuntu 10.04 or OpenSolaris 0906.
Related posts:
You might be familiar with Six Sigma business management strategy which is employed by variety of the companies in relationship to managing quality of its product. Six Sigma applies to number of defects - when you have reached six sigma quality in your production you would see 99.99966% of the products manufactured with no defects, or in other words there is less than 3 defects per million.
One of principles of six sigma is what customers tend to be concerned about variance a lot more than average. For example if you produce tomato soup and the average difference from declared weight is going to be 0.1 gram or 0.5 gram, probably nobody would not notice the difference. What would worry people however is significant number of very large differences, such as half empty tomato soup can.
You can see …
[Read more]Wow, 15 years ago, on June 8th 1995, Rasmus announced PHP 1.0. Time for a personal look back:
I can't remember when I first went online. Out from the local BBS
systems into the wide open net. It must have been around the same
time. But soon I figured out that I needed my own homepage, so I
created one, using black fonts on a green (#00ff00) background. I
was proud. The only issue: I had no idea how to make it
accessible to others, I had the HTML file local on the PC, but
well, I still was proud. I was proud since the effect of this
HTML with a little bit of JavaScript was way stronger than most
of my BASIC stuff I did before.
A bit later, in 1998, a cousin brought a magazine about writing Perl CGI applications which caught my attention so I started learning about CGI and Perl and all the …
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A few months ago, I reviewed MySQL Admin Cookbook. Today I am
reviewing High Availability MySQL Cookbook from Packt Publishing
by Alex Davies. Overall, I found the book to contain some
good hidden Gems.
The book is a mixture of MySQL Cluster (NDB), Replication
schemes, some performance tuning, some minor kernel tweaking, and
some more exotic approaches to common High Availability problems.
Overall, I found this book very informative and a good
read.
Now the specifics, the book starts out on NDB and stays focused
on this fact for about 60% of the book. The next 20% is on mySQL
replication then about 10% of the book is on tweaking kernel,
mysql, network settings to get the most out of …
In a few scenarios, I prefer using the data-type TIMESTAMP of MySQL, with the flag ON UPDATE CURRENT_TIMESTAMP. This is much easier and even faster than using a trigger which sets a specified column to NOW() or CURRENT_DATE(). I love this feature, when it comes to set last modified flags of tables. Now, I encountered a problem with a tagging table by using the flag. Every tag in the table has besides the tag-name, also the aggregated number of relations and a timestamp of last update (or the insert). Everything is okay, until you want to update the aggregated column, when the numbers are wrong for any reason.
If you have a wedding photography website, more than likely you want to showcase your work, or the work of your colleagues. You want to do this, without putting up low quality pictures, nor do you want to make your visitors wait 20 seconds before the page loads. Here are two plugins I use for my clients to help with this.
We had a one of our slave servers frequently stop replicating with the “Innodb Lock Wait Timeout” error. The slave IO thread would continue to fetch the binlogs while the slave SQL thread kept stopping with the above mentioned error. The teams initial inclination was to change the innodb lock wait timeout variable from 50 secs to a higher value. It was a read-only slave. Our expectation was there would be no competing writes. Then we started listing what are the next steps possible and what could be wrong.
While we were working on the system, we noticed that there were few select queries that …
[Read more]This time OSI Days is doing special theme around Open Source Databases. Please see their call for paper below. It will be interesting to see how many MySQL papers are being presented there. I am submitting a couple of them. Please spread the word so that we can see an increased MySQL participation there. I think they are sponsoring quite a bit of speaker travel and accommodation.
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Open Source Databases | OSI Days 2010 is the premier FOSS Databases conference being organised at Asia's largest Open Source Conference - OSI Days 2010. We invite you to come and lead a tutorial / session or participate in Panel Discussions at OSI Days 2010 on a specific Open Source Database. The last date for submitting a proposal is 25th June 2010.
The conference is scheduled for …
[Read more]While calculating the storage requirements in NDB, extra consideration is needed when calculating storage requirement for NDB tables. For tables using the NDB cluster storage engine, there is the factor of 4 – byte alignment to be taken into account when calculating storage requirements. This means that all NDB data storage is done in multiples of 4 bytes.
For Example, let’s say if a column takes 14 bytes to store. In NDB it requires 16 bytes to store. 2bytes will be padding. Because of this only in NDB TINYINT, SMALLINT, MEDUMINT, and INT all require 4 bytes storage per record due to the alignment factor. This rule is not applied in case of BIT data type.
BIT(X) – in NDB storage engine this column will take X bite of storage space, if a table definition contains 1 or more BIT column (up to 32 BIT columns) then NDB Cluster reserves 4 Bytes (32 bytes) per row for these . If the table definition contains more than 32 BIT …
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