If foreign keys are a part of the database namespace, why is it that you have to ALTER TABLE to add and remove them? Why not alter the database? I suspect the issue is more in MySQL’s limitations that names of foreign keys be unique among tables in a database. . . but it does make me wonder.

If foreign keys are a part of the database namespace, why is it that you have to ALTER TABLE to add and remove them? Why not alter the database? I suspect the issue is more in MySQL’s limitations that names of foreign keys be unique among tables in a database. . . but it does make me wonder.

Slashdot | MySQL CEO Mårten Mickos Answers Your Questions

I’m pretty sure this is the first time I’ve been mentioned by name in the 1st commet to a /. article. Yay me!? :)

As email is *sooo* non-”Web 2.0″, i reply in blog form….
Rusty’s Bleeding Edge Page talks about a “Writing an x86 hypervisor: all the cool kids are doing it!” session that sounds really cool (better not be on at the same time as my talk… :)

I don’t (currently) intend to be one of the cool kids though.

He also mentions a session entitled “First-timer’s Introduction to LCA”. A couple of possible suggestions (or thoughts, and stuff I’ve seen):

• be careful if you intend to bitch endlessly about a piece of software - it’s quite likely you’re talking to the person who wrote it (or a chunk of it)
• sometimes it can be really good to just listen and ask a few good questions to understand. there are a lot of really smart people about
• you will (at some point) ask a really dumb …

Ok, someone came in #oracle on freenode and wanted a query that would give him a distinct set of rows, where it did not matter if a values is in the first or second column.

Here is a sample table:

CREATE TABLE t (
  a int(11) NOT NULL,
  b int(11) NOT NULL
);

INSERT INTO t (a, b) VALUES (1, 2);
INSERT INTO t (a, b) VALUES (2, 1);
INSERT INTO t (a, b) VALUES (3, 4);
INSERT INTO t (a, b) VALUES (3, 6);
INSERT INTO t (a, b) VALUES (4, 3);
INSERT INTO t (a, b) VALUES (6, 3);

The output should be something like:

(1, 2), (3, 4), (3, 6)
OR
(2, 1), (3, 4), (3, 6)
OR
(6, 3), (2, 1), (3, 4)
etc ..

You get the drift ..

A self join solves the challenge, though we were wondering if any RDBMS out there could do it without a self-join by just using funky analytic features. Any RDBMS specific magic goes (except for implementing a join inside a stored procecure of course). Lets see what …

Unlike fellow author Giuseppe of last week’s Log Buffer #12 I volunteered for the job of this week’s Log Buffer. Lots to say, so little time, so lets get started with Log Buffer #13.

Tom Kyte has been at the DBForum 2006 in Denmark. Apart from the contents of the Forum, his picture and comment “I spied some artifacts from Mogens Oracle Museum, a copy of the Version 3 and Version 4 Oracle” in Dbforum 2006, in the past… was an impressive look back in time. Manuals, what are they? So how old is this? Wikipedia …

Like fellow friends and MySQL’ers before me Morgan, Roland, Giuseppe, Markus and Sean, I’ve joined the MySQL juggernaut on the ride of my life, achieving two of my short/medium term professional goals in one step. Woot!

It says something to me about the company I’m very excited to work for when I knew of all these people before they joined MySQL this year (2006). I’ll also be joining other friends and MySQL people Arjen, Jon, …

Some time ago, I sent an internal message to all the MySQL employees challenging/pleading for anyone who had coding skills but was not involved on the development team to jump in and help fix bugs. Several kind people took me up on that challenge, and Jay has now blogged about his experience and the steps involved in fixing a MySQL server bug. It’s an excellent and detailed explanation of how to set up your linux (or Mac) development environment, and how to add a test case to our regression test suite to be sure the bug never comes back. One suggestion - I recommend using compile-pentium-debug-max instead compile-pentium-debug, as the max build script turns on a lot more things in the code which you want to be tested when you run the regression test suite.

Hmm, I wonder if anyone would …

Lorenzo has startet working on better charset support in MDB2. He has added basic support for setting charsets and collations inside field definitions in CVS already. However, there are still plenty of open questions to look at. I have only limited experience with charsets in MySQL. Lorenzo has some experience with Firebird and PostgreSQL. But this is no where near sufficient to come up with a solution that would work reasonably well across all supported drivers. Check out his charset RFC on his blog. Comments are very much appreciated, even if they just highlight problems without giving a solution just yet.

For certain evil purposes last week, I assembled the old Saturn with a hard disk I found when cleaning a little while ago (I have that kind of tech stuff - you clean up and find 40GB disks - I’m pretty sure I have an 8.4 bumming around somewhere too).

I ended up being able to do the evil I needed to, but I could tell that the room was a bit warmer due to the extra box being alive. I was also lazy and couldn’t be bothered going downstairs for the D200, so this was shot with my old and trusty Coolpix 4500.

I used the box to be able to get remote access to a customers’ test setup to do some diagnosis on a bug (that’s notoriously hard to reproduce). I think I have a fair idea of what it is now though (timing related - not fun).

Remember kids, threads are evil.

Also, an interesting thing to …