This is the 159th edition of Log Buffer, the weekly review of database blogs. Welcome.

MySQL

Sun’s Trent Lloyd cautions Watch out for hostname changes when using replication!, for there is a gotcha there.

Justin Swanhart was also in the cautioning business this week, saying Be careful with BETWEEN clauses, because the MySQL optimizer is not smarter than a fifth grader!. The readers say, that’s SQL.

Anyway, it’s probably unwise to underestimate the intelligence of a child. …

In record time, less than a week after the conference (thanks to the free Pinnacle Video Spin and YouTube), all 11 videos that were taken at OpenSQLCamp Europe are online.

For those who missed the sessions, or just want to relive the fun!

Almost all the sessions were filmed; regrettably Darren Cassar’s Securich – MySQL user administration and security made easy! and Stephane Combaudon’s Minimizing data access with covering indexes were not.

The YouTube videos have the descriptions and resources from the official conference pages, and links to pages. If there is more information to add (for example, the slides from a talk are now online), or if …

This is the 158th edition of Log Buffer, the weekly review of database blogs.

SQL Server

Simon Sabin has a TSQL Challenge – counting non zero columns. He says, “I’m working on a project where I need to cycle a flag amongst a set of columns. To achieve this I am storing a position value in each column which allows me to cycle them . . .  So the challenge is to find out the how many non zero columns there are, the twist is to use as little code as possible.”

On a cue from Simon, Aaron Bertrand shares …

Welcome to the 157th edition of Log Buffer, the weekly, cross-platform review of database blogs.

SQL Server

We start with Michelle Ufford, the SQL Fool, who gives us the poor (wo)man’s graph, a fast and ingenious way to create handsome text-based graphs.

What is the importance of running regular consistency checks? Paul S. Randal returns with some survey results and analysis. He writes, “The results are actually surprising – I didn’t expect so many people to be running consistency …

Welcome to the 156th edition of Log Buffer, the weekly review of database blogs.

Oracle

Jonathan Lewis gets things rolling with his post, Empiricism. Jonathan asks his readers if an empirical approach to tuning would be appropriate for a particular wait scenario.

Doug Burns was also looking into wait times, beginning, “Sometimes you think a subject is understood so well, including by yourself, that you tend to overlook it until asked to explain it. That which seems intuitive to us …

It’s been just over three months since the April 2009 MySQL Users Conference and Expo. It took a while for the files to be processed, and then uploaded to www.technocation.org, and then I found out that the online streaming was not working properly. So I started playing with things, re-encoding some videos, updating the software, but to no avail.

Just as I was about to give up I got notification that Technocation, Inc. was accepted into YouTube’s not-for-profit program, which allows movies larger than 10 minutes to be uploaded and viewed advertisement-free.

So then I had to upload the videos to YouTube and add descriptions.

So with no *further* delay, here are all the videos from the 2009 MySQL Conference and 2009 MySQL Camp:

The brief description — just the playlists:
Conference …

This is the 155th edition of Log Buffer, the weekly review of database blogs.

SQL Server

On the SQL Server blogs this week, CSS SQL Server Engineers demonstrated that using DateDiff can query performance problems in SQL 2005 and 2008.

The kind of problems, perhaps, that Linchi Shea examines in his post on linked server security configuration and how it can hurt you. Linchi writes, …

I think many people truly realized how much they take the MySQL documentation for granted during the recent multi-hour outage from mysql.com’s data center. Apparently there is a lot of FUD floating around about the legality of mirroring the documentation, as presented by Justin Swanhart and asked by Mark Callaghan.

The manual page at http://dev.mysql.com/doc/refman/5.1/en/copyright-mysql.html says:

You shall not publish or distribute this documentation in any form or on any media, except if you distribute the documentation in a manner similar to how Sun disseminates it (that is, electronically for download on a Web site with the software) or on a CD-ROM or similar medium, …

OpenSQLCamp 2009 is happening “in parallel to the Free and Open Source Conference 2009 (FrOSCon) on Saturday 22nd and Sunday 23rd August in St. Augustin, Germany …. close to Bonn and Cologne.”

I plan on being at FrOSCon and OpenSQLCamp. Where I go before and after that is up to *you*. Yes, that is right, perhaps I will visit a user group, such as France’s MySQL User Group. Or perhaps your company needs the type of services Pythian can offer — we can do the “traditional consulting” model where we look over your systems for performance tuning and security gains, or fix problems in an emergency. Even more of a win, we specialize in recurring engineering — we can supplement your existing IT staff with database expertise, and do all the database work your current …

Welcome to the 154th edition of Log Buffer, the weekly review of database blogs. Let’s dive right in, shall we?

Oracle

On Radio Free Tooting, Andrew Clarke says, “No SQL, so what?” taking as his keynote something Nuno Souto said: “ . . . Google, Facebook, Myspace, Ning etcetc, and what they do as far as IT goes, are absolutely and totally irrelevant to the VAST majority of enterprise business.”

Aman Sharma gives an overview of Library Cache on Arista’s Oracle Blog.

On The Dutch Prutser’s Blog, …