Today while waiting at the airport, I took a look at the news stand, and right there on the cover of Fast Company were two words Google, and Wikipedia. Given Wikipedia is a poster boy of MySQL it was an immediate purchase just to see what was being said.

So the title of the cover was Google’s worse nightmare - Wikipedia’s Jimmy Wales has his sights set on the search business.

Now, often I use Wikipedia to search for things directly rather then using Google. I’ve found it usually to be more accurate, particular on topics I know it will contain. References to search users being disappointed, Google and Yahoo tied with a 2.3 of 5 in user satisfaction hits about home for me as week, and that’s exactly the ideas …

Today I was doing some pre-release testing of our software and to test it I was needed three separate servers running MySQL. After some thinking I decided to use my “old” workstation (actually it is pretty powerful Sempron with 2Gb of RAM, but now I use my macbook as a primary workstation) and start 3 separate virtual servers there. Of course, as all admins, I’m little bit lazy and installing Debian on all three machines was not appropriate solution ;-). So, I’ve created one machine, installed brand-new Debian Etch there and then begun to look for solution to clone this machine to run it in three copies. After all these operations were done, I’ve decided to spend time I’ve saved with this simple trick to describe here how to clone VmWare …

As I write this blog I have over 90 draft blog posts. That’s 9-0. Why do I have so many posts? The main reason is I want to say something, and I’ve either not completed it, or researched it sufficiently to consider the entry complete.

This frustrates me as sometimes I just want to get the word out on something, or of my opinion, or of something great I’ve discovered. I do it for me, I don’t really care if anybody actually reads my stuff, but I’m surprised sometimes when I get comments how people actually get to see my blog.

JotThat is a surprisingly simple yet brilliant idea. It’s quite simply a site for making Jots, making quick notes, making a passing comment, noting a thought, something you want to either remember or something you want to say in a simple Jot form.

What makes JotThat in my eyes? Well it’s simple, …

So, I’s been a long time since I wrote my last post here. Lots of work and almost no new interesting technologies in my work caused such delay. But today I’m proud to announce release of really interesting project: MySQL Master-Master replication manager - set of flexible scripts for management different MySQL deployment schemes with master-master replication involved.

More information about this software could be found in detailed announce in Peter Zaitsev blog (actually this software was created by me for his company’s client) or at project page. All your questions and suggestions welcomed in …

I leaned a new trick today with LOAD DATA INFILE. I’m migrating some data from an external source, and the Date Format is not the MySQL required YYYY-MM-DD, it was DD-MMM-YY. So how do you load this into a Date Field.


$ echo "02-FEB-07" > /tmp/t1.psv
$ mysql -umysql
USE test;
DROP TABLE IF EXISTS t1;
CREATE TABLE t1(d1 DATE);
# echo "02-FEB-07" > /tmp/t1.psv
LOAD DATA LOCAL INFILE '/tmp/t1.psv'
INTO TABLE t1 (@var1)
SET d1=STR_TO_DATE(@var1,'%d-%M-%y');
SELECT * FROM t1;
EXIT


The trick is to bind the appropriate column within the file being loaded to a variable, @var1 in my example and use the SET syntax to perform a function on the variable. Rather cool.

A good tip to know.

On Thursday I saw something I’d not seen before. An Empty Innodb Status. Now given the amount of output normally shown it was certainly a first. And it looked like:

mysql> SHOW ENGINE INNODB STATUS;
+--------+------+--------+
| Type   | Name | Status |
+--------+------+--------+
| InnoDB |      |        |
+--------+------+--------+
1 row in set (0.03 sec)

To answer some of the most obvious questions.

• Yes it was a working existing MySQL instance, with InnoDB correctly configured. Indeed we had been benchmarking for several hours.
• MySQL Server was running, indeed a command selecting data from the mysql schema worked just fine after seeing this (All other tables were Innodb).
• Absolutely nothing in the host MySQL error log. (This was the second most disappointing aspect)
• The Process List showed two queries that had been running for some time, everything was taking  ; 1 second. …

For all those instant GUI people out there, there is an easy way to watch the present status of your MySQL Slaves using the watch command.

$ watch -n 1 -d "mysql -uroot -pxxxx mysql -e 'SHOW SLAVE STATUS\G'"

The watch provides a view of a file or command, and shows interval updates to this output (-n  seconds> option). You can also specific a granularity better then one second for example 0.5. -d also highlights the differences for you. So while you see the following output with your SHOW SLAVE STATUS, on a loaded system you will also see bin-log and relay-log changes, and perhaps Seconds_Behind_Master.

The question is, Why is Seconds_Behind_Master the last column in this display?


*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: localhost
Master_User: repl
Master_Port: …

I got an email today from O'Reilly today about the MySQL Conference (coming up at the end in April), it looks like a pretty good conference, but one of the sessions caught my eye. It was called A Storage Engine for Amazon S3.

Amazon's S3 is a web apt-oriented storage service, making storage available to both ordinary HTTP browsers and to sophisticated applications via SOAP and REST interfaces. Learn how useful it is to make this storage accessable to MySQL users via a plug-in storage engine.

I did some quick googling but I couldn't find the plugin, so I am guessing that it will be released at the conference. Anyone have a link?

This gets interesting when combine this with Amazon EC2, because you are not charged for bandwidth from within amazon's network, and you are connected to S3 on a fast network.

With my very heavy travel load and skilling load I’ve not had time to scratch myself. It hasn’t stopped the brain working overtime on various issues including the classic find a pattern in a string starting with a wildcard character. On a recent gig I saw the true classic.


SELECT columns
FROM users
WHERE username LIKE '%str%'
OR firstname LIKE '%str%'
OR lastname LIKE '%str%'

I went through the various options and comments on leading ‘%’, OR’s, combined columns, FULLTEXT (which doesn’t work in this case), merge indexing etc, however it perplexed me that nobody has really solved this problem, or at least shared their solutions.

I have an idea, a theory and while I’d love to prove/disprove it, I simply just don’t have the time. So here are my notes, hopefully somebody can comment positively/negatively, do some research, or encourage me to pursue it more. …

** This is an editied “re-post” of an item i wrote about a year ago. **

MySQL V5.0 has been out for a while; the current production community version is 5.0.27.

With version 5, MySQL has addressed most of the major objections people have that MySQL is not a “real” database. With support for triggers, stored procedures, views and XA transactions, I think MySQL has a feature set that will enable people to easily migrate to MySQL. At this point in time, InnoDB is the only storage engine choice for applications that require transactions, and this is still a reasonable choice in most cases.

The only open question for MySQL A.B. is resolution of the problems created by Oracle’s acquisition of Innobase Oy, the developers of the InnoDB storage engine. I previously wrote a post about the Oracle Innobase issues, the summary is that Oracle’s acquisition of Innobase Oy is a problem not because of the storage engine, but …