So you have seen my writings on MySQL on Windows. Most recently regarding MySQL 5.5 and before that on Cluster and 5.1. So, what is the deal? Am I a mean person attacking MySQL? Am I a Windows hater trying to show how badly Windows works? Or maybe a Linux / Unix hater who want to keep those bearded 1970's terminal junkies out of my GUI Windows world?

Actually none of those. My ambition is to point out this that should be addressed in MySQL for Windows to make it more Windows friendly, for Windows users and developers. As MySQL on Windows stands right now,, it is OK for the Linux / Unix user user who also wants to run on Windows, and for those with cross-platform knowledge and ambition who want to run MySQL across the range. And I put myself among those. But I also want the Windows hard-core users to find out about, use and love MySQL. And MySQL sure could do much more in that area, but before that happens, we (yes we. We who are cross …

Working with customer, I faced pretty nasty bug, which is actually not rare situation , but in this particular there are some lessons I would like to share.

The case is pretty much described in bug 55981, or
in pastebin.

Everything below is related to InnoDB-plugin/XtraDB, but not to regular InnoDB ( i.e in MySQL 5.0)

In short, if you use big BLOBS ( TEXT, MEDIUMBLOB, etc) (that allocated in external segment in InnoDB), you can get your database in trash state just executing update on row with blob and rolling back transaction twice ( on the same row)

The keywords that diagnose you hit this bug is

InnoDB: Serious error! InnoDB is trying to free page N
InnoDB: though it is already marked as free in the tablespace!
InnoDB: The tablespace free …

Erin and Mike, organizers of SF Meetup generously invited me to talk on coming SF Meetup on Dec-14 about new features in InnoDB in MySQL 5.1 and 5.5 and, what is pay attention to, when you upgrade from MySQL 5.0.
Although I personally mostly in 5.1->5.5 upgrade area, Erin insured me that upgrade from MySQL 5.0 is still actually question for many users, so I accepted invitation. Event details are on Meetup.com page. So if you are up for free pizza, soda and do not mind to listen to me, welcome to join!

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MySQL 5.5 is currently in the Release Candidate phase and making good
progress on the way to being a Generally Available release. There
are many new features that will improve performance, make service
more robust, and generally make life better for DBAs. But since
5.5.7 was released for evaluation in October, there has not been a
lot of attention given to the changes in authentication.

To greatly simplify, MySQL has a table with a list of users and a
list of hosts from which those users are allowed access. So user
'jones' and the host they connect from are checked to make sure they
are allowed access. If they match, they can access the instance.

As of 5.5.7, MySQL authentication now supports pluggable
authentication and proxies. So now you can use PAM, Windows native
authentication, LDAP, or something similar to control user accounts.
Or …

Some time ago I was asked to do a study of our most popular open source projects to assess 1) what governance models are out there and 2) if the governance model has any effect on the project's success (such as size of developer community) on the one hand and on the other hand on the business of the related vendor(s). Some of the results are quite remarkable and have general applicability, so I wanted to share them here:

read more

With the standard data warehousing queries we have a fact table and dimension tables and we join them.
For example, the fact table (Table size: 5M rows, ~2G in size) from my previous Loose index scan vs. covered indexes in MySQL post:

    CREATE TABLE `ontime_2010` (
      `YearD` int(11) DEFAULT NULL,
      `MonthD` tinyint(4) DEFAULT NULL,
      `DayofMonth` tinyint(4) DEFAULT NULL,
      `DayOfWeek` tinyint(4) DEFAULT NULL,
      `Carrier` char(2) DEFAULT NULL,
      `Origin` char(5) DEFAULT NULL,
      `DepDelayMinutes` int(11) DEFAULT NULL,
      `AirlineID` int(11) DEFAULT NULL,
      `Cancelled` tinyint(4) DEFAULT NULL,
    ... more fields here ...
    ) ENGINE=InnoDB DEFAULT CHARSET=latin1

(this is not the best possible fact table as the data is not aggregated by I’ll use it for now).

And we have those …

Here you find information about OUTER JOINs in MySQL statements. This tutorial is a general introduction. Syntax details and example statements are split into a LEFT OUTER JOIN tutorial and RIGHT OUTER JOIN tutorial because these are specific outer joins. 

Outer Join basics

MySQL supports outer joins. They identify matching rows that are stored in two different tables and add the selected columns to the result set. That’s exactly what an inner join does as well.

The difference between inner and outer join is: An outer join can identify rows without a match in the joined table. When …

I am finally a citizen of the world. I beat out the 85% statistic in which American's from the USA do not venture out of the USA. I flew into Paris spent 5 days, then went to Brussels (1 day), Amsterdam (2 days), flew to Barcelona had to stay there a day because Venice was on strike, then to Venice (2 days). From Venice to Rome (5 days), then to (day trip) Naples, Pompeii, back to Rome then back to Paris and finally home.

I can go into detail of how awesome this trip was but I am going to focus on how recharged I am. Man am I! During my travel times I geeked out and read the MySQL 5.1 Plugin Development book by Sergei Golubchik and Andrew Hutchings, which is AWESOME!

Now that I am back I hope to put the things I learned from Plugin Development into action and write posts about them.

Some Posts in the next couple of weeks that I am going to focus on. SQL optimizations, Optimizer problems in 5.1, Stalls, …

I've been going through our bugs database to compile a list of some noteworthy patch contributions that have been included in the MySQL 5.5 release. Of course any contribution is appreciated, no matter how small! And the list is probably not complete — please let me know if I'm missing any. I omitted a number of smaller patches that fixed compile issues and I only considered contributions that were tracked in our bug database and were tagged as "Contribution".

Note that these are new patches that have not been part of any other MySQL release — of course, all contributions from previous releases are included in 5.5 as well. We also received a few patches for InnoDB (particularly by Mark Callaghan and his team mates at Google/Facebook), which were incorporated in the InnoDB plugin in MySQL 5.1 (and …

Hello from Birmingham, UK! I'm here to attend and speak at the UKOUG Technology & E-Business Suite 2010 conference (what a name!) We actually have two packed tracks of MySQL Sessions this Wednesday, including a keynote by Richard Mason (Vice President of MySQL Sales and Consulting at Oracle) about Oracle's strategy and plans for MySQL as well as highly technical sessions about MySQL High Availability, Scalability and Performance tuning from experts in the field. Ronald Bradford, Oracle Ace Director and long-time MySQL community advocate will also be there, speaking about …