Good morning Percona Live visitors! Attached to this post you can find a spreadsheet (both LibreOffice or Excel, as you prefer) that you can use towards the end of my tutorial. I've also attached the slides so you can download a copy of them.

Every few months, I get the fun job of announcing what’s new in TokuDB®, but this time is special. With Version 7, TokuDB for MySQL and MariaDB is going open source.

The free Community Edition is fully functional and fully performant. It has all the compression you’ve come to expect from TokuDB. It has hot schema changes: no-down-time column insertion, deletion, renaming, etc., as well as index creation. It has clustering secondary keys. We are also announcing an Enterprise Edition (coming soon) with additional benefits, such as a support package and advanced backup and recovery tools.

Making TokuDB open source is a natural next step for Tokutek’s involvement in the MySQL community. So far, Tokutek has been involved in the community in many ways:

• We’ve contributed a number of  …

To recover a dropped or corrupt table with Percona Data Recovery Tool for InnoDB you need two things: media with records(ibdata1, *.ibd, disk image, etc.) and a table structure. Indeed, there is no information about the table structure in an InnoDB page. Normally we either recover the structure from .frm files or take it from some old backup.

A new tool sys_parser can recover the table structure from InnoDB dictionary.

Why do we need a new tool anyway? It is absolutely critical to have an accurate table definition to ensure a successful recovery. Even an unnoticeable difference like NULL or NOT NULL can shift all values by a byte and thus will spoil the result. That’s why I prefer the structure from .frm …

If the following items items describe what you need in a high-availability solution, then MySQL Cluster is for you:

• High scale, reads and writes
• 99.999% availability
• Real-time
• SQL and NoSQL
• Low TCO

And what better way to get started on MySQL Cluster than taking the authentic MySQL Cluster training course.

In this 3-day course, you learn important cluster concepts and get hands-on experience installing, configuring and managing a cluster. Some events already on the schedule for this course include:

Switching roles

To get a taste of the power of Tungsten Replicator, we will show how to switch roles. This is a controlled operation (as opposed to fail-over), where we can decide when to switch and which nodes are involved.

In our topology, host1 is the master, and we have three slaves. We can either ask for a switch and let the script select the first available slave, or tell the script which slave should be promoted. The script will show us the steps needed to perform the operation.

IMPORTANT! Please note that this operation is not risk free. Tungsten replicator is a simple replication system, not a complete management tool like Continuent Tungsten. WIth the replicator, you must make sure that the applications have stopped writing to the master before starting the switch, and then you should address the application to the new master when the …

Intro

Tungsten Replicator is an open source tool that does high performance replication across database servers. It was designed to replace MySQL replication, although it also supports replication from and to Oracle and other systems. In this article, we will only cover MySQL replication, both simple and multi-master.

Preparing for installation

To follow the material in this article, you will need a recent build of Tungsten Replicator. You can get the latest ones from http://bit.ly/tr20_builds. In this article, we are using build 2.0.8-167.

Before starting any installation, you should make sure that you have satisfied all the prerequisites. Don't underestimate the list. Any missing …

I may retract this post, I may have been way too incorrect here, not sure yet.

Hash maps were invented sixty years ago, apparently. MySQL reinvented them.

Original idea was too fancy and too good, I guess. It allowed very cheap access to data, if you knew a key, and it achieved that by having a hashing function, which is used to pick a slot, then going directly to that slot. It is used in your computer all the time. ALL THE TIME.

They are so fast and useful, that they are always treated as building blocks. There have been various iterations later, to support concurrency, hashing functions evolved, etc, but the premise was the same.

If we look at the dictionary, it is obvious that “hash” is:

a mixture of jumbled incongruous things; a mess.

Yes, MySQL, the whole concept is to have as messy as possible data …

To support the growing emphasis on real-time operations, MySQL is releasing a new MySQL Applier for Hadoop to enable the replication of events from MySQL to Hadoop / Hive / HDFS (Hadoop Distributed File System) as they happen. The MySQL Applier for Hadoop complements existing batch-based Apache Sqoop connectivity. This developer article gives you everything you need to get started in implementing real-time MySQL to Hadoop integration.

A few years ago, I asked to check with me in the long (very long) change history of MySQL 5.5 documentation what are the changes in relation to the SQL syntax.
Chris Calender helped me to retrieve a list of the main changes, thanks again Chris.

Today, I would like to share this list with you.
It is simply a curated transcript of what you might find in the documentation but I’m sure it can help some of you.
 

INTO clause in nested SELECT statements

 
Previously, the parser accepted an INTO clause in nested SELECT statements, which is invalid because such statements must return their results to the outer context. As of MySQL 5.5.3, this syntax is no longer permitted and statements that use it must be changed.
 

Table aliases in DELETE statements

 
In MySQL 5.5.3, several changes …