Although a few posts have already been made about this, I thought I’d post a nice quick article by Peter Gulutzan and Dmitri Lenev on what to do with the upcoming daylight savings time changes and MySQL. This is in case you aren’t using the OS for your time zone info. You can find this out by issuing the following query:


SELECT @@global.time_zone;


If you get back ?SYSTEM?, then the MySQL server is looking to the OS for timezone data, which is the default setting.

DAYLIGHT SAVING TIME CHANGES
By Peter Gulutzan and Dmitri Lenev

This year many American states and Canadian provinces will switch to daylight saving time on March 11 (the second Sunday of March) instead of switching on the first Sunday of April as happened during previous years.

If you populated the mysql.time_zone_transition according to the instructions in the MySQL Reference Manual, “ …

Long time no blogging! I hope PlanetMySQL finally picks up my posts again, I really miss the additional audience

We recently received a request from the OpenISR project about adding the Eclipse public license to our FLOSS License Exception. As it turns out, it is almost identical to the Common Public License (CPL), which was already included in the exception. So the decision was fairly easy - version 0.6 of the FLOSS License Exception now also covers the Eclipse public license.

What is the FLOSS License exception all about anyway? Our intent:

We want specified Free/Libre and Open Source Software applications to be able to …

Your common-cold-bedeviled editor tardily submits the 35th edition of Log Buffer, the weekly review of database blogs, for your perusal. Starting with the latest about The DisaSTer™ (may or may not be real disaster), Herod T., Yet Another Oracle DBA, elaborates on his rant of last week with the provocative question, “When did oracle start [...]

Let the open source IPO market begin in earnest! With MySQL gearing up for an IPO, and this Sourcefire offering set to go [PDF], life continues to look good for open source exits. Sourcefire is issuing 5,770,000 shares at the price of $15 (which I'm hearing floating around) at a $350M valuation. Not bad.

But one thing that has me concerned is how Sourcefire apparently treats open source. LIke something to be exploited, but not replenished and fed. (I stress "apparently" because it may well be that the company does a wide range of things for the community. I'm just going off the prospectus.)

In the prospectus, Sourcefire cites the open source community as one of its primary strengths:

The Snort user community, with over 100,000 registered users and over 3 million downloads to date, has enabled us to …

So, I'm playing with 5.0.33 and there are a few gotcha:

If you use innodb and like to backup your databases using ibbackup, make sure your license is for ibackup-3.0. 2.0 will report that the iblog files are corrupt.


Otherwise it's a straight forward upgrade for me, so far.

I have a mysql 4.0 database that was about 200GB in size, most of that data was removed yet the ibdata file is still 200GB. So, what I did was

mysqldump --single-transaction -uroot -p --all-databases --master-data=1 > all_databases.sql


once backed up I trashed the old datafile and rebuilt it into an empty 5.0 datafile.

Next I added the option innodb_file_per_table so, I can shrink data on a table basis in the future.

mysql -uroot < all_databases.sql

wala done.


In a few hours I turned that 200 GB datafile into 27 …

After quite some months of silence, here is finally a new post on SQLbusRT.

The SQLbusRT project was actually the final project of the Master program I was in, and the last months have been very hectic. But, luckily I've succeeded, because on the 23rd of February I received my Master degree!

Click here for the slides of my final presentation. Unfortunately for some of you, these slides are in Dutch.

There is still a lot of work to be done in the SQLbusRT project. We would like to investigate the use of temporal and/or active databases, efficient query handling, request priority, matching of similar queries and much more. For this we are looking for one or more new Master students willing to take SQLbusRT to the next level.

If you are a Dutch Bachelor or Master student, and you are interested in a final project on …

Today I booked (well, I did that a couple of days ago) and paid for my flight ticket to the 2007 MySQL Conference & Expo. As always, its the last day for staff to get their stuff together, so I did :-)

Now, all you folk out there, might find that if you register by March 14 (I believe thats in the US timezone), you’ll save $200, so thats a total cost of only $1,295! Its at the Santa Clara Convention Center, so stay at the Hyatt if you’re wanting to hang out with MySQL’ers even after hours. Alternatively, if you’re looking for other (cheaper?) accomodation, there’s the Hilton across the road.

I’d recommend the tutorial day, especially if you’re interested in Cluster, as my friend and colleague Stewart Smith is doing the …

…whoever wrote this patch:

Server version: 5.0.33-log flupps build (probably not stable…)

Type ‘help;’ or ‘\h’ for help. Type ‘\c’ to clear the buffer.

mysql> use world;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> SELECT * FROM country, city, city c, city c2, city c3;
^CQuery aborted by Ctrl+C
ERROR 1317 (70100): Query execution was interrupted
mysql>

It doesn’t abort the client to Control-C now, just the query…
Swwwweeeeeeetttttt…….

The other day I managed to send off what’s nearly the final patches for adding proper timeout support to the MySQL Cluster management API. Jonas has had a bit of a look, found one thing I’ve missed, but it’ll probably get in somewhere soon (probably the carrier grade edition first, then others… 5.1 makes sense IMHO if only for the amount of management server testing that my patches add).

Unfortunately in what we laughingly call the past the management server - for whatever hysterical raisins - never really received much direct testing. Sure, if the data nodes couldn’t get configuration, autotest couldn’t control the daemons or something then things were obviously broken. But, say, a subtle (or not so much) change in API or behaviour would certainly not be picked up.

Although the real “feature of the year” (not my words) is fault injection for the management server that we can use in testing. The MySQL Cluster …

People across North-America are scrambling to update their servers, in order to deal with the upcoming timezone changes.

I'll tell you a little secret that has served me well... ever since the C libraries were a pest in the mid eighties (the ones on DOS defaulted to GMT-5, US EST, or something in that realm), and since with layers of libraries you easily risk missing a timezone conversion, or get double/triple conversions, I decided to never use timezones on servers again.

In the old DOS days, the library issues were resolved by making an app do setenv("TZ=GMT0"); tzset(); on startup. No more conversion problems, regardless of the system time.

But in essense I do the same on Internet servers that I manage. They all simply run in GMT and therefore never need to change timezones - and they're immune to dst funnies invented by George W Bush, too ;-)

On display, an application simply converts …