After Dublin, our next stop on the World Tour was Sweden. While several MySQLers were out on travel (in Dublin, amongst other places!) related to the Sun-MySQL integration, we had the opportunity to meet with Swedish MySQL employees from various parts of the organisation, including Sales, Engineering, Support, and Internal IT.

Yesterday’s dinner at Domtrappkällaren was a memorable one, with an opportunity to share war stories and anecdotes with our Sun colleagues Dave Douglas and Julie Ross. They got their fair share of tales from past MySQL Developer Meetings (ah, Prague! ohh, Sorrento!) and Staff Meetings (you wouldn’t believe what happened to this new guy in Sales on his first day, when arriving at his hotel room in Cancùn).

Equally important, we took time to look at what will happen next. Swedes will in short order be on-boarded, which involves everything form signing papers to getting their first salary from Sun, as …

If you’ve ever worked in companies with 5-10+ servers and it was your responsibility to install new boxes, change some configuration files and install new software on many boxes you definitely know how painful this work is. Every time you need to change something on 3-5-100 boxes, you go there and make those changes. Most experienced of us used some weird scripts to perform some task on many boxes or used some stuff like dsh. Even with those tricks I’d never wish this work to anyone.

While I was working in Galt, I’ve asked our junior admin to check out puppet and try to use it on our servers. After a week of screaming he’s managed to install and configure it and …

My wife has a site that needs two WordPress blog installations. The URLs differ by a subdirectory name. Both blogs need to be (URL-wise) subdirectories of /blog/. They need to be completely independent of each other, yet use the same custom theme. And there used to be just a single blog, which was not in a subdirectory; its permalinks must not break. (It has nice URLs with the date and title in them, not post ID-style URLs). And because I’m the husband, I get to maintain it, so tack “easy to maintain” onto the requirements (it must be easy to upgrade WP in both blogs, for example). In this article I’ll show you how I did it with a single .htaccess file, a single copy of WordPress, two MySQL databases, and a single configuration file.

Fixing URLs

As I mentioned, there used to be a blog at /blog/ which must not break. Suppose this blog was about dogs and my wife has recently started blogging about cats. She wants two …

I’ve been waving my hands about lower bounds.  Well, sometimes I haven’t been waving my hands, because the lower bounds are tight.  But in other cases (lenient insertions, range queries), the lower bounds are very far from what we’re used to.

So now, for a bit of math:

Brodal and Fagerberg showed in 2003 that there’s a tradeoff between insertions and queries.  The insertions they consider are lenient.  Well, any lower bound for lenient is a lower bound for strict, but they also gave upper bounds, so it matters.  Also, they don’t know from lenient, but if you look at their upper bound, they are implementing lenient insertions.  The queries they consider are, unfortunately, point queries.  That’s too bad for us, because we’ve already seen that point queries are just too slow to be of interest on hard disks.

Still, they have matching upper and lower bounds, so let’s see …

Since my previous laptop is temporarily out of service, I am using a new one with Mac OS X Leopard. Which is cool, and it has great enhancements. However, after a few hours of usage, I noticed a sudden increase of CPU activity (+50%), for no apparent reason.
The resource monitor fingered a process named "mdworker", and Google took me to a page explaining that the real culprit is spotlight, which is indexing the disk contents.
Since I needed all the CPU power of my laptop to compile the latest server, I asked Google again, and I found a page with a method to disable Spotlight permanently. The recommended method involves root access, changing attributes of a long list of files, and a reboot. (!!!)
I could not afford the luxury of a …

I accidentally created a TEMPORARY table in a non-existing database the other day:

localhost:(none)> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema | 
| test               | 
+--------------------+
2 rows in set (0.00 sec)

localhost:(none)> create temporary table x.xy (c int);
Query OK, 0 rows affected (0.00 sec)

localhost:(none)> desc x.xy;
+-------+---------+------+-----+---------+-------+
| Field | Type    | Null | Key | Default | Extra |
+-------+---------+------+-----+---------+-------+
| c     | int(11) | YES  |     | NULL    |       | 
+-------+---------+------+-----+---------+-------+
1 row in set (0.00 sec)

I've opened this bug: http://bugs.mysql.com/bug.php?id=35234 against the issue. I'm not sure this is really a MySQL bug (hence the …

Today, I posted the solution (a sample project) for the NetBeans 6.0/6.1 Inserts Updates Deletes tutorial using MySQL.  I'll be posting solutions for other databases on this page.

This tutorial is a JSF application that demonstrates basic CRUD (create, read, update delete) operations on a database.
 

Since about 20 months after start, a solution for Bug#12713 finally reached the main tree.
If you're not using stored functions this may have a very little effect on you, since other than fixing the problem at hand it was no more than a cleanup of the execution flow and the server/storage engine interaction. Anyway, it was a difficult one, one out of a dozen of design gotchas we added to the server with 5.0. The all-time record for that sort of difficult bugs
is Bug#989, reported back in 2003 and planned for a fix in 6.0 only.

I wrote about this in a comment to Tip of the Day ? What MySQL Version to Use by Keith Murphy, but I think it's worthy a separate post and perhaps a little debate. I'm interested to hear what other community members think of this *now*.

Keith noted that he runs builds by Sun-MySQL, since the various distros are often far behind in terms of the MySQL server version they provide. Commenters noted that Debian does backport security fixes, but sticks with older versions. It's also the case that Ubuntu actually uses very recent versions.

I feel that generally, security patches are not the main issue for production servers, since they have no direct external exposure (that may be debatable, and please feel free to comment on this!). While security in this type of environment is not completely unimportant, I feel that fixes for functional problems are …

Hiring a MySQL DBA can be challenging, especially when the demand for MySQL DBAs is greater than there are qualified people to fill those positions. This article will go into some details on how to recruit, recognize, and interview a great MySQL DBA. (For the rest of this article, MySQL DBA and DBA are the same.)


1. Preparation

It's very important to determine your company's needs before starting your search for a DBA. Is your company a small start up, or a mature company that has a large replicated or clustered environment? Is this DBA position needed to support developers? Will this position support 24/7 operations? Will a smart candidate be able to learn as they go, or do you need a rockstar now that can handle your requirements from day one? By brain storming with various department managers or technical staff, the requirements will become clear as to what's expected for this position. Just like a software …