With its distributed, shared-nothing, real-time design, MySQL Cluster has attracted a lot of attention from developers who need to scale both read and write traffic with ultra-low latency and fault-tolerance, using commodity hardware. With many proven deployments in web, gaming, telecoms and mobile use-cases, MySQL Cluster is certainly able to meet these sorts of requirements.

But, as a distributed database, developers do need to think a little differently about data access patterns along with schema and query optimisations in order to get the best possible performance.

Sharing best practices developed by working with MySQL Cluster's largest users, we recently ran a Performance …

This past week I attended OSCon, the annual conference for open source’s true believers. And there was a religious fervor in the air, particularly from the point of view of someone more accustomed to Oracle conferences.

And if open source is the religion, proprietary closed-source companies are the devil. That having been said, I was surprised how virtually all large companies were demonized. Even long-time defenders of open source like IBM were ignored at best. That didn’t prevent them from coming though, with Microsoft and HP in particular with high-profile sponsorships and PR offensives that didn’t seem to have much influence with the crowd.

The companies generating buzz were the small companies built around development of their own open source products. There are a surprising number of them out there, especially relating to multiple forks of a popular product like MySQL or …

Meet The SkySQL Team At OSCON 2012!

“I remember my first OSCON in 2001 and the passionate debates we had on the impact the open source movement was going to make …”

This is a quote from a conversation that some SkySQLers were having this week in Paris, where we met to discuss the future - ours and that of the MariaDB & MySQL databases as well as open source technologies in general!

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Earlier this week we all read GigaOM's article with this title:
"Why the days are numbered for Hadoop as we know it"I know GigaOM like to provoke scandals sometimes, we all remember some other unforgettable piece, but there is something behind it...

Hadoop today (after SOA not so long ago) is one of the worst case of an abused buzzword ever known to men. It's everything, everywhere, can cure illnesses and do "big-data" at the same time! Wow! Actually Hadoop is a software framework that supports data-intensive distributed applications, derived from Google's MapReduce and Google File System (GFS) papers.

My take from the article is this: Hadoop is a foundation, low-level platform. I used the word …

Can OLTP database workloads use Amazon S3 as primary storage? Now they can, thanks to the Cloud Storage Engine (ClouSE), but the question is: how fast?

• ClouSE on “across the street” vs. “across the continent” cloud storage
• ClouSE vs InnoDB
• ClouSE benefits

To answer the question about performance, we decided to run db_STRESS benchmark on a MySQL database in Amazon EC2.  We compared 3 configurations:

• “Across the street storage”: ClouSE with data stored in S3 in the same …

What do you think of this piece of C code?

  void foo(long v) {
    unsigned long u;
    unsigned sign;
    if (v < 0) {
      u = -v;
      sign = 1;
    } else {
      u = v;
      sign = 0;
    }
    ...

Seems pretty simple, right? Then what do you think of this output from MySQL:

  mysql> create table t1 (a bigint) as select '-9223372036854775807.5' as a;
  mysql> select * from t1;
  +----------------------+
  | a                    |
  +----------------------+
  | -'..--).0-*(+,))+(0( | 
  +----------------------+

Yes, that is authentic output from older versions of MySQL. Not just the wrong number, the output is complete garbage! This is my all-time favorite MySQL bug#31799. It was caused by code like the above C snippet.

So can you spot what is wrong with the code? Looks pretty simple, does it not? But the title of this post …

In a previous post I wrote ARM based servers. Since then, and thanks to all the comments and responses I got, I looked more into this ARM thing and it's absolutely fascinating...

Look at this beauty (taken from the site of Calxeda, the manufacturer):

What is it? A chip? A server? No, it's a cluster of 4 servers...

And this:

is HP Redstone Server, 288 chips, 1,152 cores (Calxeda quad-core SoC) in a 4U server “Dramatically reducing the cost and complexity of cabling and …

I’ve been working on a data archival project over the last couple weeks and thought it would be interesting to discuss something a bit counter-intuitive. Absolutes are never true, but when getting rid of data, it’s usually more efficient to insert the data being kept into a new table rather than deleting the old data from the existing table.

Here is our example table from the IMDB database.

mysql> show create table title\G
*************************** 1. row ***************************
       Table: title
Create Table: CREATE TABLE `title` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `title` text NOT NULL,
  `imdb_index` varchar(12) DEFAULT NULL,
  `kind_id` int(11) NOT NULL,
  `production_year` int(11) DEFAULT NULL,
  `imdb_id` int(11) DEFAULT NULL,
  `phonetic_code` varchar(5) DEFAULT NULL,
  `episode_of_id` int(11) DEFAULT NULL,
  `season_nr` int(11) …

New quick-start guide for MySQL DBAs: SkySQL™ Enterprise Monitor makes managing your MySQL & MariaDB databases that much easier

We’ve just published a new Quick Start Guide to SkySQL™ Enterprise Monitor for all MySQL & MariaDB DBAs out there, who are looking for ways to manage their databases more easily.

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There are mistakes that drive you crazy when you try to understand what went wrong.

One of the most annoying and hard to catch was this, apparently harmless line:

tungsten-sandbox -m 5.5.24 --topology all-masters -n 2 -p 7300 -l 12300 -r 10300 –t $HOME/mm -d tsb-mm

The person reporting the error told me that the installation directory (indicated by "-t") was not taken into account.

I usually debug by examples, so I copied the line, and pasted it into one of my servers. Sure enough, the application did not take trat option into account. The installation kept happening in the default directory.

I knew that I had done a good job at making the application configurable, but I checked the code nonetheless. The only place where the default directory is mentioned is when the related variable is initialized. Throughout the code, there are no literal values used for this purpose. And yet, the …