Among other things, these past few months I have been working on setting up Buildbot, including adding various enhancements and bug fixes that are needed to properly build and test the MariaDB and MySQL code base.

Since Buildbot is written in Python, this means I have also had to learn Python. I am an old-time Perl hacker, so this exercise feels a bit like living in enemy territory ;-)

Anyway, Python is often touted as a more "pretty" language. And in many ways it is. Still, it is not without its own gotchas. Think "scope rules". Obviously someone haven't been reading up on the subject before implementing things in Python, causing the language to behave stupidly (and certainly different from what one expects) in the following three cases that I hit during my Buildbot work.

First …

Shortly after I created the initial packages of embedded InnoDB on the OpenSUSE Build Service, Oracle/Innobase released an updated version (1.0.3.5325). In addition to many improvements and bug fixes, they slightly changed the versioning scheme to better indicate what version of the InnodDB plugin their code is based on (see Vasil's posting on the InnoDB Forums for more information).

I've now updated my InnoDB packages on the Build Service to this version as well - please note that the naming scheme of the shared library package has …

Introduction

StackOverflow is an amazing site for coding questions. It was created by Joel Spolsky of joelonsoftware.com, Jeff Atwood of codinghorror.com, and some other incredibly smart guys who truly care about user experience. I have been a total fan of SO since it went mainstream and it's now a borderline addiction (you can see my StackOverflow badge on the right sidebar).

The Story

Update 6/21/09: This server is currently under very heavy load (10-200), even with caching plugins enabled. Please bear with me as I try to resolve the situation.

Feel free to …

After a long hiatus, I am happy to announce that mylvmbackup version 0.12 has now been released. This release includes a large number of improvements, minor code cleanups, as well as some new functionality. In particular, I would like to thank Matthew Boehm, Tim Stoop, Baron Schwartz, Ville Skyttä and Ronald Bradford for their contributions.

Some notable highlights from the ChangeLog:

• Removed the absolute path names to external tools (make sure $PATH is correct)
• Added --log-err to the startup options of the recovery instance to avoid cluttering the server's error log
• Added support for hooks written as Perl Modules. (Matthew Boehm)
• Added support for date/time-formatted path names for backupdir and mountdir (Matthew Boehm)
• Backupdir and …

Introduction

A question I recently saw on Stack Overflow titled Faster way to delete matching [database] rows? prompted me to organize my thoughts and observations on the subject and quickly jot them down here.

Here is the brief description of the task: say, you have 2 MySQL tables a and b. The tables contain the same type of data, for example log entries. Now you want to delete all or a subset of the entries in table a that exist in table b.

Solutions Suggested By Others

DELETE FROM a WHERE EXISTS (SELECT b.id FROM b WHERE b.id = a.id);

DELETE a FROM a INNER JOIN b on a.id=b.id;

DELETE FROM a WHERE id IN (SELECT id FROM b)

The Problem With Suggested Solutions

Solutions above are all fine if the tables are quite small and the …

On my last count, there are now 20+ Sun Contributor Agreement (SCA) signatories whose names appear on the master list and who are interested in contributing to MySQL. Only this week, three new members signed the SCA.

These 22+ signatories have all been added since mid-February when we launched the new, Sun-compliant SCA signing process. Before the end of 2009, if we proceed at this same rate, MySQL SCA signatories list should grow to about 70 to 90 contributors.

In the meantime, contributions from many of these contributors have already been accepted and integrated. (I had earlier pointed to Armin Schöffmann's contribution as a simple example of how all this works.)

Some people continue to …

On my last count, there are now 20+ Sun Contributor Agreement (SCA) signatories whose names appear on the master list and who are interested in contributing to MySQL. Only this week, three new members signed the SCA.

These 22+ signatories have all been added since mid-February when we launched the new, Sun-compliant SCA signing process. Before the end of 2009, if we proceed at this same rate, MySQL SCA signatories list should grow to about 70 to 90 contributors.

In the meantime, contributions from many of these contributors have already been accepted and integrated. (I had earlier pointed to Armin Schöffmann's contribution as a simple example of how all this works.)

Some people continue to …

On my last count, there are now 20+ Sun Contributor Agreement (SCA) signatories whose names appear on the master list and who are interested in contributing to MySQL. Only this week, three new members signed the SCA.

These 22+ signatories have all been added since mid-February when we launched the new, Sun-compliant SCA signing process. Before the end of 2009, if we proceed at this same rate, MySQL SCA signatories list should grow to about 70 to 90 contributors.

In the meantime, contributions from many of these contributors have already been accepted and integrated. (I had earlier pointed to Armin Schöffmann's contribution as a simple example of how all this works.)

Some people continue to …

MySQL provides a SOUNDEX() function, which returns the soundex of a given string. For details, refer to the manual, but to put it simply, it allows you to compare strings based on how they sound, hence letting you do proximity searches on your database. If you’re just querying for a word, it’s usage is pretty […]

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Kazuho Oku of Cybozu Labs, Inc., a community contributor to MySQL and SCA signatory, gives a talk on Q4M, a message queue stroage engine for MySQL.