Kris travels
Pending acts of god, I will be
- at the MariaDB Dev Meeting in Lisbon, PT, arriving 2011-03-11 (Thu) late, and leaving 2011-03-14 (Mon) around noon
- at O'Reilly MySQL Conference and Expo in Santa Clara between 2011-04-12 and 2011-04-15. I will arrive in SFO late 2011-04-08.
Salmiakki - the official MySQL Drink

The official MySQL Drink. How to make it:
LDAP is not relational
My thinking was that the topic is already dead, but people have strange ideas off and on again. Have a look at the S9Y boards where you'll find someone who wants to have a storage backend "LDAP" for S9Y. This is sick and wrong! Let me explain why.
Continue reading "LDAP is not relational"
Continue reading "LDAP is not relational"
How to blog for a planet
Hmm. Planet MySQL was close to unreadable for me this morning. Also, I had a technical discussion on writing style with a colleague just a few weeks ago, so I might as well take what I explained to him and put it into a form suitable for Planet MySQL. Please note that this is how I see things. This may or may not coincide with Arjen's view or the view of MySQL AB.
If you write blog entries for a blog that is being picked up by a planet, you are writing for a larger audience that for your own blog, and that audience may have other goals and intentions than regular readers of your blog. Here are a few things to keep in mind:
Regular readers of your blog are coming specifically to you because they share a lot of interestes with you regarding the topics you cover. You can go into a lot of depth and you can assume a lot of context.
When your blog is being picked up by a planet, things are different - a lot different.
The planet that picks up your entries is for its readers an overview of an entire field, often aggregating the RSS feeds from more than a hundred blogs. For the readers of the planet, the planet is the morning news, starting their workday. The planet will contain a lot of articles, some of them of no interest at all to the reader, some of them of cursory interest ("interesting to know that this feature exists") and some of them right on target. The objective of the planet is to aggregate news on a subject or field of interest, and to provide a daily overview to the planets readers.
The planet will link to your articles, and that is where you can provide the depth.
This has a few implications on your writing style in your own blog:
If you write blog entries for a blog that is being picked up by a planet, you are writing for a larger audience that for your own blog, and that audience may have other goals and intentions than regular readers of your blog. Here are a few things to keep in mind:
Regular readers of your blog are coming specifically to you because they share a lot of interestes with you regarding the topics you cover. You can go into a lot of depth and you can assume a lot of context.
When your blog is being picked up by a planet, things are different - a lot different.
The planet that picks up your entries is for its readers an overview of an entire field, often aggregating the RSS feeds from more than a hundred blogs. For the readers of the planet, the planet is the morning news, starting their workday. The planet will contain a lot of articles, some of them of no interest at all to the reader, some of them of cursory interest ("interesting to know that this feature exists") and some of them right on target. The objective of the planet is to aggregate news on a subject or field of interest, and to provide a daily overview to the planets readers.
The planet will link to your articles, and that is where you can provide the depth.
This has a few implications on your writing style in your own blog:
- Make sure your blog has facilities for you to distinguish between teaser and article body.
- Make sure you feed only the teaser to the planet, and not the full articles body.
- Make sure you are writing the teaser in a way that it can be rendered "context free". That is, make sure the teaser markup is self-contained and makes no essential refereces to stylesheets or other layout objects only present on your blog. It should look good in your blogs template, but it must also be reasonably readable in the planets template.
- Make sure you are writing the teaser in a way that in can be understood "context free". That is, make sure you are writing the teaser for the casual reader. Make clear, what the article is about and why a planets reader should have a glance of the rest of the article. Who is your intended audience, when should they read your article and what do you expect them to know beforehand? What will they learn?
- Keep the teaser short. The planet can only work properly if you provide room for 2-3 teasers to be visible in the planets layout at the same time.
Sakila's Secret
Kai Voigt was making jokes about the secret MySQL underwear. Carol made it real: From the Sakila's Secret Shop we bring you the MySQL Boxers ($10, Cash only).
Not using port 25 to send mail
When you are a road warrior, you will be using a lot of different internet connections from a lot of different providers. Sending your mail can be an adventure, because more and more services block outgoing connections using port 25 in order to prevent infected machines from sending spam.
Fortunately, there are alternatives, and I am not talking webmailers here. Most company mailers and freemail servers now offer their services on ports 587 (submission) and 465 (smtps) as well.
Submission is basically SMTP with AUTH SMTP requirement moved to a different port. Very often it is combined with STARTTLS for encryption to protect the passwords transported in authentication. You can test submission manually using the openssl command line client, if you are using openssl 0.9.7 or higher:
To test SMTPS (SMTP via SSL tunnels), try this instead:
Most mailers, including Thunderbird and Kmail, have no problem at all dealing with these mailer definitions, or will even use them automatically if you check the "use TLS" or "use SSL" checkboxes with them.
Also note that IMAPS (port 993) and POP3S (port 995) are also available with most services. We do have 2006. Unencrypted communication is never necessary, and a hotel firewall should not be blocking you from phoning home.
Fortunately, there are alternatives, and I am not talking webmailers here. Most company mailers and freemail servers now offer their services on ports 587 (submission) and 465 (smtps) as well.
Submission is basically SMTP with AUTH SMTP requirement moved to a different port. Very often it is combined with STARTTLS for encryption to protect the passwords transported in authentication. You can test submission manually using the openssl command line client, if you are using openssl 0.9.7 or higher:
$ openssl s_client -starttls smtp -connect smtp.web.de:587This will start a regular SMTP dialogue with the web.de SMTP AUTH mailer on port 587.
To test SMTPS (SMTP via SSL tunnels), try this instead:
openssl s_client -connect mailsend.mysql.com:465
Most mailers, including Thunderbird and Kmail, have no problem at all dealing with these mailer definitions, or will even use them automatically if you check the "use TLS" or "use SSL" checkboxes with them.
Also note that IMAPS (port 993) and POP3S (port 995) are also available with most services. We do have 2006. Unencrypted communication is never necessary, and a hotel firewall should not be blocking you from phoning home.