I have a somewhat strange relation to parser since a while. Like everyone I started with writing little parsers by hand and bounced several times against yacc and flex failing to get around their very own syntax.

Then I discovered lemon and used it in lighttpd for the configuration and HTTP parsing, finally a parser syntax I could read. But it still was a split between lexing and parsing.

Along the the way there was ragel with its wonderful dot-output to visualize its state-engine, very neat and a mixed lexer and parser.

2-3 weeks ago I finally stumbled over LPEG and I'm happily writing parsers now. Like a simple one that can parse complex SELECT queries and …

mysqlsla v2 is finally “done” and released. About 3 months ago, when v1.8 was released, I said it would be coming “soon,” but time just flew by and here we are. Oh well. In any case, the v1 branch is dead to me and v2 is all the rave (at least for me). If you don’t care about the differences and all you want is your default top 10 report from a slow log, for example, then all you need to know is: mysqlsla -lt slow SLOW_LOG

For those interested in what has changed to warrant a new major version number, here’s the briefing of changes/overhauls:

1. Almost ALL new command line options (–log-type a.k.a. -lt is the most important); see the documentation
2. Customizable reports. In v1 the report was hard-coded. Now with -rf FILE you can format your own report. See the …

Last November, I wrote an article describing an idea I had for a game/website.
Here is a short recap:

I wanted to make a web-based text game called Shadow People. Shadow people will be a game to do with government agencies and spy organizations.
There will be two different groups of agencies: Government owned/regulated ones and Terrorists/Freelance ones.
If it helps you imagining how it will look like, if anyone saw the series “"La Femme Nikita" with the actress Peta Wilson.
The game revolves round the cool and secret world of small yet highly effective organizations that either try to keep order in the world or cause chaos.
These organizations have the highest skilled personal, best equipment possible and will stop at nothing till they get what they came for.
Since then, I've been.. well.. busy …

The Payment Card Industry Data Security Standard (PCI DSS) has been developed to help organizations that process card payments to prevent credit card fraud, cracking and various other security vulnerabilities and threats.

This has been developed by the major credit card companies such as MasterCard and Visa. If one of the companies that created the standard, Mastercard International uses PCI General for MySQL then you would be confident that the software is of the highest quality to satisfy all requirements.

A few questions to consider.

Q: Why is PCI compliance important?
A: Credit Card companies will start to demand organizations that store credit card numbers have adequate security of their (as in the credit card company) data.

Q: How can I support PCI …

I know it's been a very long time since I posted anything, but I felt the itch today. A question came up earlier this week at work: How much is JOIN performance affected when using columns that are not the exact same data type?

This is important for me because entity-attribute-value tables require a lot of self-joins. Let me start by saying that we mitigate one of the common drawbacks to EAVs - mashing diverse data types into a single column - by separating numeric, date, and character data into different tables. However, we mashed a lot of integer data into a DECIMAL(13,4) column right alongside our financial data. I recently noticed that most of the data in this EAV table has no fractional part, and to determine whether it would be worth moving it all into another table - as well as determine what column type to use - I spent an afternoon running …

A web app full of data is often going to be full of tables (at least on the administration end). A listing of users here, all the recently created events there. Often for readability we will alternate rows between two slightly different background colors.This can be handled on the PHP end with a bit of math and a counter, like so:$count = 0;while( $row = mysql_fetch_assoc($res) ) {    if( $count % 2 == 0 )         $background_color = 'white';    else        $background_color = 'gray';    /* OUTPUT TABLE CONTENTS WITH GIVEN BACKGROUND */    $count++;}However, it can also be done entirely in-database, via creative use of the XOR operator: ...

This week, database blogs seemed to talk about conforming to stereotypes as well as breaking them.

Fulfilling the stereotype of Microsoft software being unsecure, Microsoft released a very important SQL Server update that Aaron Bertrand notes patches “four elevation of privilege vulnerabilities.” That’s right, not one, not two, but four!!! At least there is a patch now……go forth and patch! Usually it is MySQL that throws ambiguous warnings or errors which are not an accurate representation of the actual error, but Bertrand also notes that there is A Little Management Studio Oops.

Contrary to stereotype, …

Introduction
MySQL® 6.0.5-alpha, the latest version of the 6.x branch of the Database Server, is available for download from the SUN|MySQL Web Site.

Metadata (data about the data) are very important, especially for software developers. In this article we will see what’s new in FALCON metadata handling doing some comparison with the old 6.0.4-alpha version.

New tables in the `information_schema` database
As you know, the source for metadata is the database `information_schema`. To start, let’s see which tables related with FALCON metadata are included in that database:

mysql> SELECT VERSION();
+—————————+
| VERSION()                             |
…

At the Red Hat Summit I was able to grab sometime with Chander Kant, CEO of open source back-up provider, Zmanda.

I had previously met Chander at the MySQL conference where they were named a partner of the year, but we didn't get a chance to talk much.  It was pretty cool to hear about how he originally identified the opportunity for Zmanda and then built a business around it.

My interview with Chander (13:27)  Listen ( …

Having a Google account is sometimes useful in ways you hadn’t planned for. For example, at a few different employers I’ve been at, I’ve had to prepare for reviews by providing a list of accomplishments to my supervisor. One decent tool for generating this list is email, though it can take some time. Another useful tool is the Web History feature of your Google account.

Though this isn’t necessarily indicative of everything I’ve accomplished in the first half of 2008 per se, it’s definitely indicative of the types of things I’ve generally been into so far this year, and it’s interesting to look back. What does your Web History say?

• Gearman - this is used by some rather large web sites, notably Digg. It reminds me a little of having Torque and Maui, but geared toward more general-purpose applications. In fact, it was never clear to me that …