Jennifer Widom just received the ACM SIGMOD Edgar F. Codd Innovations Award, and spoke about the process of database research:
"[I]t's imperative to think about all three of the critical components -- data model, query language, and system -- and in that order! We in research have a rare luxury, compared to those in industry, that we can mull over a data model for a long time before we move on to think about how we'll query it, and we can nail down a solid syntax and semantics for a query language before we implement it."I've designed languages before, and I know how hard it is to do it right, so when I was designing SQLstream's extensions …

I was asked recently by a client to help with providing a history of data in certain tables. Like most problems, there is no one single solution, and in this case there are several possible solutions. I was able to provide a database specific only solution, with just minimal impact to the existing schema.

Here is my approach, your feedback and alternative input as always a welcome.

The problem

Client: I want to keep a history of all changes to two tables, and have a means of viewing this history.

For the purposes of this solution, we will use one table, called ‘customer’ from the Sakila Sample Database.

Solution

For tables to be audited, we will introduce a new column called ‘audit_id’ which is NULLABLE, and hopefully will not affect any existing INSERT statements providing column naming (a Best Practice) is …

(Reposted from Zack Urlocker’s blog)

Andrii Nikitin, one of the MySQL support engineers located in Ukraine, has asked for help from MySQLers and so I’m sharing this information to the community at large. Andrii’s son Ivan, who is 2 1/2, is in need of a bone marrow transplant operation. This will require going to a clinic in Europe that will not be covered by regular insurance. So Andrii has aksed to see if we could help raise funds. The cost is expected to be 150,000 - 250,000 EUROS. A huge amount for an engineer from Ukraine to cover. But a small amount by many people could make a big difference.

Many MySQLers have kicked in to help out, but more is needed. Ivan’s health has taken a turn for the worse recently and the issue is now quite pressing. Even a small donation could mean the difference between life and death for Ivan.

I hope some of you who use MySQL or have young kids will join me in making a …

Last Friday and Saturday I had the pleasure of presenting DRBD-based high availability at the 2008 Zarafa Summer Camp. What’s this Zarafa thing, you ask? Here’s a quick introduction.

Zarafa is a fully LAMP-based, drop-in replacement for Microsoft Exchange developed by a Delft, Netherlands-based company. Yes, that means that all those Windows desktop users out there can use their beloved Microsoft Outlook to connect to a full-fledged collaboration solution, including email, calendaring, contact management, a global address book, and task sharing. Using native MAPI. And the server components are 100% built on Linux, Apache, MySQL, and PHP. They even use an …

Jim, where are you when we need you?

"Jim," of course, is Jim Whitehurst, CEO of Red Hat. The need? To get more enterprises contributing back to open source. Forrester has found that--Surprise! Surprise!--most enterprises consume open source but don't contribute back to it.

This isn't surprising, nor are the reasons and means of adoption:

"...[O]pen source adoption initially focused on the operating system and Web server tiers of the application platform stack, but early success widened the focus to include development tools, infrastructure components such as application servers and databases, and higher-level components such as portal servers and content management systems."

Lower cost was the main driver for open …

Jim, where are you when we need you?

"Jim," of course, is Jim Whitehurst, CEO of Red Hat. The need? To get more enterprises contributing back to open source. Forrester has found that--Surprise! Surprise!--most enterprises consume open source but don't contribute back to it.

This isn't surprising, nor are the reasons and means of adoption:

"...[O]pen source adoption initially focused on the operating system and Web server tiers of the application platform stack, but early success widened the focus to include development tools, infrastructure components such as application servers and databases, and higher-level components such as portal servers and content management systems."

Lower cost was the main driver for open …

Andrii Nikitin, one of the MySQL support engineers located in Ukraine, has asked for help from MySQLers and so I'm sharing this information to the community at large.  Andrii's son Ivan, who is 2 1/2, is in need of a bone marrow transplant operation.  This will require going to a clinic in Europe that will not be covered by regular insurance.  So Andrii has aksed to see if we could help raise funds.  The cost is expected to be $150,000 - $250,000.  A huge amount for an engineer from Ukraine to cover.   But a small amount by many people could make a big difference. 

Many MySQLers have kicked in to …

It's no secret that Sun just laid off 1,000 employees, and may lay off up to 2,500, but what is interesting is how Sun is offsetting the headcount loss with a more efficient way of finding leads.

It's called open source. As TechCrunch reports on Sun CEO Jonathan Schwartz's Supernova talk:

His talk was about how Sun leverages open source by allowing its software (such as MySQL and ZFS) to float out and be downloaded for free, from where a small percentage of those users can be converted to customers. So through open source and free, Sun have the benefit of a free lead generation and marketing machine - especially with MySQL which is currently being downloaded over 70,000 times a day.

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It's no secret that Sun just laid off 1,000 employees, and may lay off up to 2,500, but what is interesting is how Sun is offsetting the headcount loss with a more efficient way of finding leads.

It's called open source. As TechCrunch reports on Sun CEO Jonathan Schwartz's Supernova talk:

His talk was about how Sun leverages open source by allowing its software (such as MySQL and ZFS) to float out and be downloaded for free, from where a small percentage of those users can be converted to customers. So through open source and free, Sun have the benefit of a free lead generation and marketing machine - especially with MySQL which is currently being downloaded over 70,000 times a day.

...

Over the last few weeks I have been doing some work on improving the concurrency performance of PBXT. The last Alpha version (1.0.03) has quite a few problems in this area.

Most of the problems have been with r/w lock and mutex contention but, I soon discovered that MySQL has some serious problems of it's own. In fact, I had to remove some of the bottlenecks in MySQL in order to continue the optimization of PBXT.

The result for simple SELECT performance is shown in the graph below.

Here you can see that the gain is over 60% for 32 or more concurrent threads. Both results show the performance with the newly optimized version of PBXT. The test is running on a 2.16 MHz dual core processor, so I expect an even greater improvement on 4 or 8 cores. The query I ran for this test is …