The sixteenth edition of Log Buffer, the weekly review of database blogs, has been published by Guy Bowerman on his blog, Informix Application Development. Log Buffer has a distributed editorship. If you’d like to share your POV on the database blogosphere, read the Log Buffer homepage and get involved. Take it away, Guy.
A bit ago ago I posted some optimizer hints and recommended using them to write more readable queries. Today I stumbled across an example of my own work that I changed. This is not quite a case of using BETWEEN instead of AND statements, but it sort of is. Basically, I needed to reuse this query:
SELECT count(*),city,
CASE WHEN lastLogin < now ()-interval 90 day THEN 90
WHEN lastLogin < NOW()-interval 60 day THEN 60
WHEN lastLogin < NOW()-interval 30 day THEN 30
WHEN lastLogin > NOW()-interval 30 day THEN 0
ELSE -1
END
FROM . . .
I wrote this query less than a month ago.
I looked at this query today and wondered, “why did I not put
lastLogin < now ()-interval 60 AND
lastLogin>NOW()-interval 90 in there?” I then realized
what I did.
Because the CASE statement …
[Read more]A bit ago ago I posted some optimizer hints and recommended using them to write more readable queries. Today I stumbled across an example of my own work that I changed. This is not quite a case of using BETWEEN instead of AND statements, but it sort of is. Basically, I needed to reuse this query:
SELECT count(*),city,
CASE WHEN lastLogin < now ()-interval 90 day THEN 90
WHEN lastLogin < NOW()-interval 60 day THEN 60
WHEN lastLogin < NOW()-interval 30 day THEN 30
WHEN lastLogin > NOW()-interval 30 day THEN 0
ELSE -1
END
FROM . . .
I wrote this query less than a month ago.
I looked at this query today and wondered, “why did I not put
lastLogin < now ()-interval 60 AND
lastLogin>NOW()-interval 90 in there?” I then realized
what I did.
Because the CASE statement …
[Read more]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.
Joke of the day from our character sets ubergod:
10:59 < bar> mysql> set names utf8; 10:59 < bar> Query OK, 0 rows affected (0.00 sec) 10:59 < bar> mysql> create table t1 (a text, 10:59 < bar> -> fulltext index `
So what am I up to?
I am taking a vacation.
What does that mean?
I am on a "Hacker Holiday"
In other words I am at staying at home and screwing around with
some technology that I have been wanting to look at.
One of the things I am trying to do is see why my network goes
down the tubes every so often (or am I supposed to now say the
Tubes get full?). I use DD-WRT , http://www.dd-wrt.com/, on all of my routers.
I got the brilliant idea of enabling QOS on Wednesday to see if I
could get better bandwidth shaping. This pretty much broke
everything... I disabled it suspecting that it was causing the
router to max out its CPU only to discover that the network
issues were related to the maximum number of open connections
that my WRT54GL can handle. Which means that I need to find a
faster box to run DD-WRT on. Problem is... I …
A week ago, I noted the following:
The MySQL 5.0.26 released 3 Oct 2006 contains an embarrassing ABI breakage. We?re fixing this bug right now, and making a new build including the first binaries which will carry the name ?MySQL Community Server? and ?MySQL Enterprise Server? (which obviously did not exist on 3 Oct 2006). We?ll notify both our community and our customers of the new builds when they?re available.
Sorry about the trouble. We?re also improving our internal QA and build processes, in order to avoid future, similar problems.
Now, we have fixed the ABI breakage and built new releases.
- MySQL Community Server 5.0.27 is built and the packages are being seeded to our mirrors. We will send a release announcement, as we’ve always done, to …
A few weeks ago, I was holding a PHP training for a customer who's using the Oracle database on a regular basis. My boss and I agreed on teaching the Oracle database connection with PDO (instead of the MySQL database connection we usually teach in trainings).
Unfakeable Linux. Red Hat responds., Red Hat (Press Release)
Oracle Joins The Free Standards Group As A Platinum Member, Oracle (Press Release)
Canonical Launches New Ubuntu Release for Desktops and Servers, Canonical (Press Release)
White-Box PC Makers Pre-Install Novell’s SUSE Linux Enterprise Desktop, Novell (Press Release)
SibylSource Offers Professional Windows-Based Open Source Desktop Suite, SibylSource (Press Release)
…
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