Seriously, it did.  Sorta.

I use Workbench for my daily work, and it’s a great tool.  If you haven’t tried the 5.2 release yet, you should.  While performing some maintenance, I happened to issue a DELETE statement against a table which had no indexes (it was 10 rows), and Workbench complained:

Error Code: 1175
You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column

It turns out this is a new feature in 5.2.26 (and is still there in 5.2.27) – Workbench now uses the equivalent of –safe-updates mode for the mysql command-line client (also known as the –i-am-a-dummy option – seriously).  This wasn’t exactly convenient for me, …

In database modeling, a m:n relationship is usually resolved by an additional table. But what if this relation is used only for archiving and the number of links in the resulting table is not too high? In that context, I got the idea to store all referring ID's as CSV string directly into a TEXT column of one of the referring tables. I came to this idea, because otherwise I would have to build complicated foreign keys and this way I also save one additional table. Certainly, this only makes sense if the data is not frequently accessed as foreign key. Nevertheless, I would like to tackle the problem, even if the implementation is very MySQL-oriented.

Read the rest »

“Hey DBA!  Remember that change you made for my group  four or five months ago? Well, we were waiting for things to get better but they have not. Can you change it back ASAP?!?”

I know several of you  DBAs after reading the above are reaching for their antacids.  OR something stronger.

Keeping track of what changes were made to which systems in your head is bound to bite a hard working DBA sooner or later.

This is one of those oh-so-obvious tips that will be ignored by many but it will come back to haunt like a cheap RAID array.   Get a notebook, a pen, and keep it by you when you work.  Now anytime you make a material change or perform a maintenance function on one of your systems, note what EXACTLY the change you made, the reason for the change,  plus the day and date.  It will take some effort to do this the first two times but you this to become an ingrained …

Not much new this time: just summary of part 3 published and fixed mistake in chapter 10 (thanks, Shane!).

Summary.

In the third part we discussed methods of application debugging in cases when query plays secondary role in the problem.

I'd like to bring your attention we only discussed most frequent cases while MySQL server has a lot of parameters which of them can affect application. Analyze parameters which you use. One of the methods is run problematic query using MySQL server running with option --no-defaults and examine if results are different for MySQL server run with parameter which you use. If results are different analyze why parameter affects it and solve the problem.

...

Rest of the chapter is …

Platform: MySQL 5.x

Most of the time it would be handy to have a native MySQL script which would allow one to kill the sleeping connections which are in sleep state for more than 180 sec..  On the other hand DBA's can use  "wait_timeout" etc parameters to control this..

[code]

 # -- Make sure you are logged as MySQL 'root' user or any user who have got super privileges 



DELIMITER $$
DROP PROCEDURE IF EXISTS `uKillSleepingSessions`$$


CREATE PROCEDURE `uKillSleepingSessions`()
COMMENT 'This routne is used to kill idle sessions'
READS SQL DATA


BEGIN


DECLARE no_more_rows BOOLEAN;
DECLARE loop_cntr INT DEFAULT 0;
DECLARE num_rows INT DEFAULT 0;
DECLARE uID bigint(4);

DECLARE my_cur CURSOR FOR
SELECT ID
  FROM …

Not much new this time: just summary of part 3 published and fixed mistake in chapter 10 (thanks, Shane!).

Summary.

In the third part we discussed methods of application debugging in cases when query plays secondary role in the problem.

I'd like to bring your attention we only discussed most frequent cases while MySQL server has a lot of parameters which of them can affect application. Analyze parameters which you use. One of the methods is run problematic query using MySQL server running with option --no-defaults and examine if results are different for MySQL server run with parameter which you use. If results are different analyze why parameter affects it and solve the problem.

...

Rest of the chapter is …

We’re proud to announce the next release of MySQL Workbench, version 5.2.27. This is the second maintenance release for 5.2 GA (Generally Available). This maintenance release does not introduce any new features, but focuses on general product improvement and usability.  We hope you will make MySQL Workbench your preferred tool for Design, Development, and Administration of your MySQL database applications.

As always, we want to thank everyone for the great feedback we have received. This helps us to continuously improve and extend the functionality and stability of MySQL Workbench – please keep up on approaching us with any ideas to develop our product even further.

MySQL Workbench 5.2 GA

• Data Modeling
• Query (replaces the old MySQL Query Browser)
• Administration (replaces the old MySQL Administrator)

Please get your copy from our Download site. Sources and binary …

Ignacio Nin and I (mostly Ignacio) have worked together to create tcprstat[1], a new tool that times TCP requests and prints out statistics on them. The output looks somewhat like vmstat or iostat, but we’ve chosen the statistics carefully so you can compute meaningful things about your TCP traffic.

What is this good for? In a nutshell, it is a lightweight way to measure response times on a server such as a database, memcached, Apache, and so on. You can use this information for historical metrics, capacity planning, troubleshooting, and monitoring to name just a few.

The tcprstat tool itself is a means of gathering raw statistics, which are suitable for storing and manipulating with other programs and scripts. By default, tcprstat works just like vmstat: it runs once, prints out a line, and exits. You’ll probably want to tell it to run forever, and continue to print out more lines. Each line contains a timestamp and …