The latest from the MySQL community

One very interesting thing I noticed with MySQL was that if you delete a database, ibdata file doesn’t shrink by that much space to minimize disk usage. I deleted the database and checked usage of /usr/local/mysql/var folder and noticed that ibdata file is still the same size. So the problem I face now [...]

Two open source funding announcements yesterday (Vyatta and Silicon Navigator) reminded me that I needed to also post the March funding announcements for Avidence and Penguin Computing.

Avidence: March 19th funding announcement (press release) of $5m in Series A by Red Rock Ventures and ArrowPath Venture Partners. Avidence is an early-stage startup in the process of developing an open source platform for digital video.

Penguin Computing: March 29th funding announcement (press release) of $9m in Series B, led by vSpring Capital, with participation from existing investors San Francisco Equity …

I guess many of you know, that using SELECT count(*) FROM table is problematic and slow when using Innodb tables.
This actually only applies to COUNT(*) queries without WHERE a clause as mentioned in the MySQL Performance Blog.

But if you got some slow count query in your application the best way to increase its performance is to replace / remove it.

So if you are going do to "SELECT count(*) FROM products" the best way, is to have a separated table
that stores the number of products. If you're inserting a row increment the counter, if you're deleting a row, decrement it.

Here is some example:
CREATE TABLE counter( number_of_products int(10) DEFAULT '0' NOT NULL);

Increment when you're adding a new product to the products table:

PLAIN TEXT SQL:

1. UPDATE counter SET …

Yesterday we had our sixth MySQL Meetup here in Hamburg - we had a nice crowd of 21 people. Erick Dennis and Michael Otto from epublica gave a presentation about their experiences with MySQL and scaling it to keep up with the growth of the Xing.com web site. The talk was a rehearsal for their presentation at the upcoming MySQL Conference and Expo in Santa Clara - it went very well and we had good discussions and comments during and after the session. I took some pictures during the meeting, which are now available on my picture gallery. The meeting was …

A few days ago a bug report was filed to the MySQL bugs system. For a few hours it was just one among the many, although it looked hard to reproduce.
Then, suddenly, two experienced contributors, Martin Friebe and Alexander Fomichev, joined the discussion, offering similar cases, explanations, a workaround, and even a patch.

The public intervention took place within 11 hours after the MySQL Engineer asked for clarifications, and within one day the solution was served!

Thanks guys!
We love it when bugs are solved this way.

Still in Japan. Today and tomorrow I am spending time with Mixi.jp,
looking at their MySQL Setup. They are the Livejournal of Japan, but
with more video and pictures!

I am going to the YAPC dinner in Tokyo tomorrow night.

Its raining, reminds me of home :)

I wrote an article late last week about benchmark results for the two table-synchronization algorithms I've been implementing for the MySQL Table Sync tool. I've spent some time developing a test suite for the tool, and learned some really interesting things about the general problem of synchronizing tables.

With last weeks release of Zimbra Desktop and our recent GA release of Zimbra for Ubuntu ( Download OSS or Network) it's now easier than ever to move your email client and server to Linux.

First you need to get your Zimbra Server up and running. Our community has been running Ubuntu for quite some time and now that it's GA our customers have the same choice. Zimbra's Network version now supports four Linux distributions (more if you count the 32bit and 64bit …

It's often quite tempting to make sweeping statements about the superiority of one approach to a problem over another. While various approaches often have advantages, in the real world often there are many competing criteria which make a black and white assessment of choices seem rather simplistic. Politicians and marketing folks oversimplify complex problems every day, and it often makes a real discussion of the issue at hand harder - although it does engender a vitriolic us vs. them approach of yelling. Luckily for us, this never happens in the technical world.

Eric Bergen posted an interesting entry on his blog this morning about DRBD. He makes some very good points, but I believe leaves out some context or assumptions for some of his conclusions, primarily by assuming that there is a single HA setup with a single set of criteria for success …

Ivan mentions the Q and As from a Q&A session in which MySQL Cluster is mentioned - I thought I’d add my perspective here as well:

Q from Matthew: When are we likely to see disk based indexing for ndb?
Disk based indexing is planned in one of the future releases, but we can’t say when we will implement it. During the webinar, Anders pointed out that he does not see this as an important thing. I tend to agree with Anders, at least considering the current status of the storage engine. At the moment, ndb can perform an unbeatable job (in terms of HA and performance) on small transactions and simple queries and we should not consider it as a full replacement for the whole database, in general. The future versions of ndb will probably be more and more general purpose and at some point a …