Recently my attention was brought to this bug which is a nightmare bug for any consultant.

Working with production systems we assume reads are reads and if we're just reading we can't break anything. OK may be we can crash the server with some select query which runs into some bug but not cause the data loss.

This case teaches us things can be different - reads can in fact cause certain writes (updates) inside which add risk, such as exposed by this bug.

This is why transparency is important - to understand how safe something is it is not enough to know what is this logically but also what really happens inside and so what can go wrong.

Entry posted by peter | 19 comments

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I'm pleased to announce the release of the Memcached Functions for MySQL, version 0.8.

This version includes a bunch of fixes for behavior setting and retrieval. You now have:

Ability to fetch a behavior:

memc_server_behavior_get();

All behaviors can be set now successfully with memc_server_behavior_set()

Boolean:

select memc_behavior_set('MEMCACHED_BEHAVIOR_BUFFER_REQUESTS', '1');

Name of a value (string):

select memc_behavior_set('MEMCACHED_BEHAVIOR_HASH','MEMCACHED_HASH_MD5' );

Numeric:

select memc_behavior_set('MEMCACHED_BEHAVIOR_SOCKET_SEND_SIZE', 60000);

Also, you can now list the distribution types to use when calling memc_server_behavior_set('MEMCACHED_BEHAVIOR_DISTRIBUTION', ''), which produces a list of all the distrubution types:

select …

Jos, my co-author for the "Building Pentaho Solutions" book just pointed me to a recent article by Jeff Prenevost entitled "The Problem with History".AbstractJeff's topic, loading a hybrid Type 1 / Type 2 slowly changing dimension table is related to data warehousing but maybe of interest outside of that context as well.

As it turns out, the particular problem described by Jeff is non-trivial, but can be solved quite elegantly in a single SQL statment. This may be a compelling alternative to the multi-step, …

In the last few months, we've introduced a few interesting new features to opentaps.

Query Builder for opentaps Analytics

We have completed a query builder for opentaps analytics, which allows you to query the opentaps data warehouse based on multiple criteria. For example, you can now run a report of sales by product for all "Gizmos" in the United States since 2007, or sales by product in California on Mondays during the Julys. This new tool, along with the data transformations, reports, and report generator we've already built, will give you a large number of available reports through opentaps analytics

Google Web Toolkit Widgets Now Officially in opentaps

We have merged back the Google Web Toolkit (GWT) …

Has anyone else noticed that almost all of the consulting companies that support MySQL (and blog) start with a 'P'? (Percona, Pythian, Proven Scaling). I think OpenQuery needs a name change to keep up with the market. Even though 'O' is the letter next to 'P' in the alphabet, it requires more than one bit flip - so it's not that close.

Has anyone else noticed that almost all of the consulting companies that support MySQL (and blog) start with a 'P'? (Percona, Pythian, Proven Scaling). I think OpenQuery needs a name change to keep up with the market. Even though 'O' is the letter next to 'P' in the alphabet, it requires more than one bit flip - so it's not that close.

The MySQL Proxy was split into

• a chassis which handles cmdline, service, logging, plugin loading
• a core library for the life-cycle, network handling and protocol decoding
• a lua layer wrapping around the internals
• a set of plugins: proxy, admin, debug, replicant

It also contains a few tools that reuse the above libraries:

• mysql-binlog-dump
• mysql-myisam-dump

We dropped libcheck in favour of glib 2.16's g_test_* functions.

Changelog:

Chassis

• added support for SIGHUP to reopen logfiles
• added win32-service support
• added --basedir
• added experimental --log-backtrace-on-crash
• added DTrace probes
• added a angel to keep the chasses alive
• added --user option to change the …

I’ve been thinking about SaaS (in the form of Spinn3r) and how it relates to Open Source for the past few months and I think I’ve come to some interesting conclusions. I think SaaS might be a strong competitor to Open Source in that it’s cheaper and higher quality in a number of situations.

Apparently, I’m no the only one:

Open source is always driven by some organisation – a central body that leads community development efforts to support developers and build revenue streams. In essence, that body gives away the base code and knowledge of the community version to encourage development of the service and expand distribution; to make the software go ‘viral’.

However, I believe software as a service …

This week we had our first WarpTalks session. Once a month we’ll gather in our meeting room and someone will deliver a talk, workshop or debate about topics considered interesting.

We opened this Monday with two talks. They are in Spanish but you can get the idea.

Introduction to Subversion by Victor Jimenez

Subversion is the RCS we currently use, and the developers know it well enough to do their everyday job, but the not-so technical people at the company have been expecting some training for a while.

Introduccion a Subversion from Jorge Bernal on Vimeo.

10 things you might not know about MySQL by Jorge Bernal (me)

MySQL is the obvious choice when we need a database for our projects, so many of the developers use …

Sun reports second quarter results. Compiere reports 216% quarterly revenue growth. EnterpriseDB grows customers accounts. Hyperic and JasperSoft team up on BI for IT. Microsoft embraces Apache but resists GPL. And more.

Sun up or Sun down?
There was some comparatively good news from Sun, which reported a net loss of $209m on revenue down 10.9% at $3.2bn. As Sam Diaz at ZDnet notes, however, “after excluding one-time costs related to recent layoffs and other costs, the company posted a profit of 15 cents per share, beating analysts’ expectations of a 10 cent loss”. In regular trading, shares of Sun were up more than 5%.

Matt Asay noted the impact open …