Ken Henderson's WebLog

This is an oldie, but a goodie. It's an article by Ken Thompson about, among other things, writing self-replicating programs. Thompson is one of my heroes and someone who's had a profound impact on the industry. His list of accomplishments is too long...

Today’s entry is another T-SQL puzzle. Steve Kass took the prize for the best solution to my last T-SQL puzzle , and several others came up with some pretty original solutions of their own. I especially liked the ones that were T-SQL specific – ones that...

I guess the other shoe has finally dropped at Borland. Chief Scientist Danny Thorpe has left. He jumped ship for Google in December . I received the news with mixed emotions. On the one hand, it’s a terrible, perhaps fatal, loss for Borland. On the other...

As I think many of you know, I'm updating my SQL Server books for SQL Server 2005. I'm currently wrestling with something that I've decided to put to a vote. The question before me is whether to include the Windows fundamentals coverage that was in the...

I read a blog by Mark Russinovich the other day that disturbed me a bit. It always bothers me when someone as highly regarded as Mark completely misses the boat because it means that a lot of other people will probably miss the boat, too. People often...

I'm interested to hear what you consider the biggest potential security issues with SQL Server 2005. I've asked previously about concerns regarding SQLCLR ; today I'm widening the net and asking about the entire product. If you have security concerns...

One of the great features in SQL Server is its optimizing query processor. The Sybase version of SQL Server pioneered on-the-fly query optimization, and, even to this day, intrinsic query optimization is one of the most useful features of the product...

I have a number of sites I frequent and do business with, but I'm sure there are plenty of great ones that I don't know about. I'm interested to hear about the ones that you visit often. Here's my list: 1. Books, CDs, and sometimes other stuff: Amazon...

It's pretty common for a complex app to make multiple connections to SQL Server. And, on SQL Server 2000 and earlier releases, it's also very easy for those types of app to cause perf problems by distributing their workload across their connections unevenly...

Many have noted that there are some files missing from the CD accompanying my latest book, SQL Server 2005 Practical Troubleshooting . My apologies for that. We’ve just posted an update to the book’s CD at http://www.khen.com/sspt.htm . Note: you’re welcome...

The simplest rule-compliant solution to the employee-mentor challenge I recently posted is to change the loop such that it iterates through the relationships at more than one speed. Making no other changes to clean up the code, something like this would...

I lamented the slow death of Borland in a recent post and was roundly assailed for it by the Borland community. I speculated that perhaps the other shoe had finally dropped at Borland with the departure of Chief Scientist Danny Thorpe, the latest in a...

Early last month, I wanted to see what it would be like to blog everyday. I wanted to see how it would work into my schedule, and I wanted to see whether it would be a positive thing in the community and something that would help people. So, starting...

Most knowledgable SQL Server DBAs know you shouldn't compress a database's data and log files, but I'll wager that few know the details behind why that's such a bad idea. The general reply might be "Performance" -- and that's correct -- but the assumption...

Given that a recent blog of mine lamented the dangers of using xprocs, I thought it would be a good time to show some of the wonderful stuff you can do thanks to SQL Server extensibility features such as xprocs and COM objects. It’s not that xprocs or...

I'm in the hospital once again with kidney stones. They have a saying in the emergency room here that the severity of the pain one typically experiences with kidney stones is similar to that suffered by women during childbirth. If that's true, it makes...

I've been hearing from some folk that they consider the SQLCLR functionality in SQL Server 2005 to be a potential security hole. Some have even gone so far as to say that they plan to leave it disabled (it's not enabled by default). When pressed, many...

According to the BOL, the recommended way of yielding to other workers in SQLCLR is to call System.Thread.Sleep(0). Long before Yukon shipped, I had a conversation with a coworker who was responsible for knowing something about SQLCLR, and I asked how...

My friend Bart Duncan is now blogging. Bart is one of the top SQL Server performance experts in the world. You can find his new blog here on MSDN at http://blogs.msdn.com/bartd .

I'm starting a new movie review blog because I wanted to get familiar with Community Server and because I thought my movie reviews really ought to be on their own site rather than clogging up my MSN Spaces blog site . They tend to be much longer than...

For those who don't have this yet, it looks like Joe is blogging: http://joecelkothesqlapprentice.blogspot.com/ Joe swears this isn't him, but I'm skeptical... Among other things, the blog features lots of pictures of Joe. I'm still waiting for...

For those interested in such things, there's a poem over on my personal blog having to do with history, politics, and religion. Enough of my friends have been stumped by it that I thought I'd post it publicly to see how many could figure out who it was...

I've mentioned before that I had a new book coming out. It's finally available on Amazon. Again, I didn't write this one; I was just its editor. It was written by a "dream team" of developers from the SQL Server dev team and support engineers from Microsoft...

Have you ever needed to find your most expensive queries and quickly grew weary of writing T-SQL against trace tables to try to ferret them out? Have you ever had to wade through gigabytes of trace data just to find one ill-behaving query? Have you ever...

A key Windows facility that’s been available since NT shipped is the support of memory-mapped files. A memory-mapped file is a file that has been mapped (i.e., not copied) into virtual memory such that it looks as though it has been loaded into memory...