The recently released MySQL 5.6 gets a lot of attention, but for those who are still on 5.5 there is also good news: There are two new features in 5.5.

The first feature is that there are more INFORMATION_SCHEMA tables for InnoDB. This means that it's possible to 'see' what's in the buffer pool. It also makes it possible to get more information about the LRU list.

From the 5.5.28 changelog:
InnoDB: Certain information_schema tables originally introduced in MySQL 5.6 are now also available in MySQL 5.5 and MySQL 5.1: INNODB_BUFFER_PAGE, INNODB_BUFFER_PAGE_LRU, and INNODB_BUFFER_POOL_STATS. (Bug #13113026)

This is in the "Bugs Fixed" section instead of the "Functionality Added or Changed" section, which is a bit weird in my opinion.

The second feature is a variable which makes it …

InnoDB Full-text Search in MySQL 5.6: Part 2, The Queries!

This is part 2 in a 3 part series. In part 1, we took a quick look at some initial configuration of InnoDB full-text search and discovered a little bit of quirky behavior; here, we are going to run some queries and compare the result sets. Our hope is that the one of two things will happen; either the results returned from a MyISAM FTS query will be exactly identical to the same query when performed against InnoDB data, OR that the results returned by InnoDB FTS will somehow be “better” (as much as it’s actually possible to do this in a single blog post) than what MyISAM gives us.

Recall that we have two different sets of …

I’ve never been a very big fan of MyISAM; I would argue that in most situations, any possible advantages to using MyISAM are far outweighed by the potential disadvantages and the strengths of InnoDB. However, up until MySQL 5.6, MyISAM was the only storage engine with support for full-text search (FTS). And I’ve encountered many customers for whom the prudent move would be a migration to InnoDB, but due to their use of MyISAM FTS, the idea of a complete or partial migration was, for one reason or another, an impractical solution. So, when FTS for InnoDB was first announced, I thought this might end up being the magic bullet that would help these sorts of customers realize all of the benefits that have been engineered into InnoDB over the past few years and still keep their FTS capability without having to make any significant code changes.

Unfortunately, I think that hope may be premature. While it is true that InnoDB FTS in MySQL 5.6 is …

This month is a special month. It’s not because of President’s Day or even the exciting day where we revel in groundhogs. No, this month is special because the free book give-away is happening again. This is where you, the reader, gets to win something free for doing nothing more than posting a comment saying that you want a copy of my recently published book – The InnoDB Quick Reference Guide from Packt Publishing. The book is a great reference for DBAs, PHP, Python, or Perl programmers that integrate with MySQL and want to learn more about the InnoDB database engine.

So, all you have to do is post a comment here saying that you want a copy and write out a single (or more) sentence about how you use InnoDB in your development or production environment. At the end of the month two readers will be chosen via a random list sorting script that …

I am very excited and thrilled to use the latest release of MySQL 5.6 in production. This is probably the most notable and innovative release in many years, if not ever.

During the last year, we had the chance to work with many new features and test the fixes to old issues. To be honest, I was expecting to have MySQL 5.6 GA before now, and I even wagered with my colleague Francisco that it would be out before the end of 2012. It was nothing special, just a beer in the Santa Clara Hyatt lounge. Unfortunately for me, MySQL 5.6 is now in GA and given that it happened in 2013, I lost the bet and now have to pay for that beer. But I have also lost the full list of things that we saw as relevant, interesting, or really innovative for MySQL.

So I took a step back, took some time, and reviewed what Oracle delivered in this new MySQL release.

Short premise

Oracle developer teams did great work for …

I’m pleased to announce that my first book, the InnoDB Quick Reference Guide, is now available from Packt Publishing and you can download it by clicking here. It covers the most common topics of InnoDB usage in the enterprise, including: general overview of its use and benefits, detailed explanation of seventeen static variables and seven dynamic variables, load testing methodology, maintenance and monitoring, as well as troubleshooting and useful analytics for the engine. The current version of MySQL ships with InnoDB as the default table engine, so whether you program your MySQL enabled applications with PHP, Python, Perl or otherwise, you’ll likely benefit from this concise but comprehensive reference guide for InnoDB databases.

Here are the chapter overviews …

“With MySQL 5.6, developers can now commingle the “best of both worlds” with fast key-value look up operations and complex SQL queries to meet user and application specific requirements” –Tomas Ulin. On February 5, 2013, Oracle announced the general availability of MySQL 5.6. I have interviewed Tomas Ulin, Vice President for the MySQL Engineering team [...]

Today my colleague Matt alerted me to an issue being discussed in the Phabricator IRC channel which was caused by a MySQL edge case that might trip some people up.

The issue is to do with how InnoDB assigns auto_increment values after restart.

Lets create two simple tables and a simple example scenario that is very similar to the Phabricator issue….

Table 1 “tasks”

      CREATE TABLE `tasks` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `task` varchar(30) DEFAULT NULL,
  `assignee` varchar(30) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

Table 2 “tasks_archive”

There are many good things in the upcoming MySQL 5.6 release. One thing that caught my eye early on was the ability to start the server with InnoDB set to a read only mode.

A few months ago Todd Farmer wrote about this ability from the perspective of setting up an instance on read-only media (InnoDB now works with read-only media). And I encourage you to read that post first.
I decided to test this from a data warehouse perspective (as Sunny Bains points out in a comment to Todd's post). I used machines I have available: 1 OL6 desktop running 5.6.9 and 1 MacBook Pro running 10.8.

First thing to try was adding the innodb_read_only parameter to the config file on an instance I already had running on the Linux box. My setting:

[mysqld]
user = mysql
port = 5602
…

In On learning InnoDB: A journey to the core, I introduced the innodb_diagrams project to document the InnoDB internals, which provides the diagrams used in this post. Later on in A quick introduction to innodb_ruby I walked through installation and a few quick demos of the innodb_space command-line tool.

The physical structure of InnoDB’s INDEX pages was described in The physical structure of InnoDB index pages, and the logical structure was described in B+Tree …