The blog title says it all: Do we need a MySQL Cookbook? I tend to think so.

This seems to be something that is missing with current MySQL documentation. There is lots of information available but finding the appropriate bit can be quite tedious and it often requires looking in multiple places.

A lot of other software has such books, but for some reason MySQL seems to be missing one.

A recent example comes from a “documentation feature request” I posted today: http://bugs.mysql.com/bug.php?id=68171. MySQL 5.6 provides a way to “move InnoDB tables” from one server to another. There are many reasons why you may want to do it, but the documentation is currently rather sparse. A simple “example recipe” for this would be good, as would an equivalent recipe for other engines where you can do this such as MyISAM. This is just an isolated …

With the MySQL 5.6 production-ready GA set for release in the coming days, it’s good to re-cap the key features that make 5.6 the best release of the database ever.  At a glance, MySQL 5.6 is simply a better MySQL with improvements that enhance every functional area of the database kernel, including:

• Improved Security for worry-free application deployments
• Better Performance and Scalability
  • Improved InnoDB storage engine for better transactional throughput
  • Improved Optimizer for better query execution times and diagnostics
• Better Application Availability with Online DDL/Schema changes
• Better Developer Agility with NoSQL Access with Memcached API to InnoDB
• Improved Replication for high performance, self-healing distributed deployments
• Improved Performance Schema for better instrumentation …

I saw a post on profiling memory usage today and this reminds me of several discussions I have had with different people.

Why would you want to profile the memory usage? Usually to see where memory is allocated and for what purposes, and usually you only care when memory usage is higher than expected. That is a DBA normally wants to use all available memory on a server for mysqld, whatever that size may be.

Configuration parameters may be inappropriate and need adjusting, so having a way to determine the range of memory usage based on those parameters would be most helpful.  However, the configuration parameters as a whole put no limit on memory used, so different workloads can quite easily lead to memory being insufficient on the OS, triggering swapping or perhaps the …

In May of last year I blogged about MariaDB 10.0 for the first time. We received some feedback, digested it, and I further explained MariaDB 10.0. Now, with the first Alpha of MariaDB 10.0 out and a new year just beginning, now is a good time to explain a little bit more, especially about MariaDB 10.0 and MySQL 5.6 as I and others in the MariaDB project get asked a lot about the differences between them.

First, here are some details as to why we didn’t just take MySQL 5.6 as a base and create something that would have been called MariaDB 5.6. These details haven’t been widely shared before:

1. The file structure of the codebase in MySQL 5.6 has changed. Single code files have been split into several and code has been …

MySQL 5.6 introduces a new features that must be used with great care. A MySQL users password can be marked as expired. This way, a DBA can force a user to set or reset his password. The MySQL user must set a (new) password before he is allowed to do anything else. As a consequence, if a users password is expired all standard PHP MySQL API connect calls will fail. Applications stop working unless the application is changed to include a user dialog for setting a new password. To develop such a dialog for resetting an expired password one has to use a new connection flag introduced in PHP 5.4.12-dev. Don’t panic: to get in trouble DBA actions have to be at one level with dropping the MySQL user of a production PHP application…

Relax: IF MySQL 5.6 AND IF …AND IF …

You are being warned in time about a pitfall that DBAs may tap into in the …

Global Transaction Identifiers (GTIDs) are one of the key replication enhancements in MySQL 5.6. GTIDs make it simple to track and compare replication across a master - slave topology. This enables:

- Much simpler recovery from failures of the master,

- Introduces great flexibility in the provisioning and on-going management of multi-tier or ring (circular) replication topologies.

A new on-demand MySQL 5.6 GTID webinar delivered by the replication engineering team is now available, providing deep insight into the design and implementation of GTIDs, and how they enable users to simplify MySQL scaling and HA. The webinar covers:

- Concepts: What is a GTID? How does the …

MySQL 5.6 seems to be ready for GA. I have no inside information about it, but from some clues collected in various places I feel that the release should not be far away. Thus, it's time for some serious testing, and for that purpose I have worked at updating MySQL Sandbox with some urgent features.

I have just released MySQL Sandbox 3.0.28, with more support for MySQL 5.6. Notably in this release, there is suppression of MySQL 5.6 annoying verbosity, additional suppression of more annoying warnings ( actually a bug) when using empty passwords on …

While testing MySQL 5.6, I came across some curious values for the new values used to set the crash-safe slave tables. To get safety, we need to set relay_log_info_repository and master_info_repository to 'TABLE'. That way, the replication information, instead of going to a file, will be saved to two tables in the mysql schema (mysql.slave_relay_log_info and mysql.slave_master_info).

So I was setting these values back and forth between 'FILE' and 'TABLE', until I made a "mistake." Instead of typing

set global relay_log_info_repository='table';

I wrote

set global relay_log_info_repository=1;

To my surprise, it did what I …

MySQL 5.6 is truly a better MySQL and reflects Oracle's commitment to the evolution of the most popular and widely
used open source database on the planet.  The feature-complete 5.6 release candidate was announced at MySQL Connect in late September and the production-ready, generally available ("GA") product should be available in early 2013.  

While the message around 5.6 has been focused mainly on mass appeal, advanced topics like performance/scale, high availability, and self-healing replication clusters, MySQL 5.6 also provides many developer-friendly nuggets that
are designed to enable those who are building the next generation of web-based …

Users are safer

MySQL 5.6.8 was announced a few days ago. You can download it from the MySQL downloads page

This is the second release candidate of MySQL 5.6, and it is strange. My understanding of a release candidate is something that is stable, its features committed long time ago, and the release will just attempt to fix bugs. Instead, there are features that were not in the first release candidate. This one strikes me as really odd (quoting from the announcement) :

On Unix platforms, mysql_install_db supports a new option, --random-passwords, that provides for more secure MySQL installation. Invoking mysql_install_db with this option causes it to perform the following actions in addition to its normal operation: …