Percona Server version 5.6.14-62.0

Percona is glad to announce the release of Percona Server 5.6.14-62.0 on October 24th, 2013 (Downloads are available here and from the Percona Software Repositories.

Based on MySQL 5.6.14, including all the bug fixes in it, Percona Server 5.6.14-62.0 is the current GA release in the Percona Server 5.6 series. …

I normally don’t write such posts, but this time I’ll do a little whining. I was looking at MySQL’s Bug#69581, which was also filed against MariaDB as MDEV-5102. With some effort (little for this particular bug), one can find out that Bug#69581’s counterpart in Oracle’s internal bug database is Bug#16862316, and the fix is in revision 5366 in MySQL 5.6.14.

There are two problems, though:

• The fix doesn’t include a testcase. We know, Oracle doesn’t publish testcases for crashing bugs, with a justification that it’s for security reasons. However, this bug is not a …

Today I wanted to take a look at improving the performance of tables that cause performance problems based largely on their size. Some of this advice also applies to databases that are large in-aggregate over many tables, but I always find the individually large table a special-case that is problematic.

What you will normally find is that the speed that the table can be modified will trend down as the size increases. Here is what I am going to call the typical B+Tree index performance over time:

This graph taken from a post by MySQL@Facebook. It shows the performance degradation of inserting one billion rows into a table with insert buffer disabled (not recommended, and used for demonstration purposes only). Note that this is in log scale!

The benchmark is called …

The General MySQL Syntax section of the MySQL 5.6 Developer certification exam is a bit meatier than the MySQL Architecture section covered in my last post, but it’s still likely to be very familiar to experienced MySQL developers (or DBAs):

• Explain MySQL implementation of identifiers including case sensitivity, qualified names, aliases and use of reserved words
• Identify MySQL data type properties and appropriate usage
• Recognize and use common functions and expressions for all MySQL data types
• Identify and use comment syntax
• Describe and utilize prepared statements
• Describe transactions and transaction isolation levels and the impact they have on database behavior

MySQL Identifiers

• MySQL treats …

There is a new release of the Connector/Arduino on Launchpad! See https://launchpad.net/mysql-arduino. The new version supports a number of refinements and a few new features. These include:

• Improved support for processing result sets
• Conditional compilation to omit result set handling features to save program space
• Support for the Arduino WiFi shield
• New version() method to check version of the connector
• Simplified download (no more patching SHA1!)

So What is It?
If you have never heard of Connector/Arduino, it is simply a library designed to allow the Arduino platform to connect to and issue queries to a MySQL Database server.

Simply add an Ethernet shield to your Arduino and use the library to connect your Arduino to a MySQL database server. Yes, no more web-based hand waving or third party systems! Cool.

New …

Dear Community,

it is my pleasure to announce that there will be a community dinner on the evening of Monday the 11th of November in London coinciding with the Percona Live Conference. In the same spirit as the community dinner in Santa Clara, the event will be `pay your own way` so it's important to bring some cash on the evening so that splitting the bill is as painless as possible.

The venue is Masala Zone in Earl's Court, which is a short walk from the Millenium Gloucester. For anyone that would like to walk over we will meet in the foyer of the hotel at ~7pm and walk over. 

Please make your way over to our eventbrite page to register your attendance so that we can give the guys at Masala Zone good notice of how many to expect.

The link above will take you to the Masala Zone site …

While integrating TokuDB into MySQL 5.6, we found that MySQL 5.6 does not support more than one XA storage engine. For example, there is an assert in the ha_recover function that fires when the total number of XA storage engines is greater than one. After disabling this assert, we found lots of bugs in the MySQL 5.6 implementation of the TC_LOG_MMAP class, which is used when running with the binlog turned off.

There are two alternatives that we know of to fix this problem in MySQL 5.6:

• First, we could merge code from MariaDB 5.5 into MySQL 5.6. The advantage of this approach is that we have been running this code with TokuDB in MariaDB 5.5 for a long time, so we have confidence in its correctness.
• Second, we found that MySQL 5.7.2 has made changes to allow multiple XA storage engines. This is great news for TokuDB since we have one less MySQL patch to worry about. Our simple scan of the MySQL 5.7 source showed …

Parallel Universe is now available as part of Linux OS images at Amazon AWS Marketplace in addition to Community AMIs.
Amazon Web Services is a scalable cloud service provider at http://aws.amazon.com available in

US East (Virginia)
US West (Oregon)
US West (Northern California)
EU West (Ireland)
Asia Pacific (Singapore)
Asia Pacific (Sydney)
Asia Pacific (Tokyo)
South America (Sao Paulo)

Launch Instance -> AWS Marketplace or Community AMIs -> search “parallel universe”

Host OS:
Amazon Linux
Red Hat Enterprise Linux
SUSE Linux Enterprise Server
Ubuntu Server
Cluster Compute Amazon Linux
Cluster GPU Amazon Linux
Cluster Instances SUSE Linux Enterprise Server
Cluster Instances Ubuntu Server

Dear MySQL users,

MySQL Connector/Net 6.8.0, a new version of the all-managed .NET driver for MySQL has been released. This is an alpha release for 6.8.x and it's not recommended for production environments.
It is appropriate for use with MySQL server versions 5.0-5.6

It is now available in source and binary form from http://dev.mysql.com/downloads/connector/net/#downloads and mirror sites (note that not all mirror sites may be up to date at this point-if you can't find this version on some mirror, please try again later or choose another download site.)

The 6.8.0 version of MySQL Connector/Net has support for Entity Framework 6.0.

The release is available to download at http://dev.mysql.com/downloads/connector/net/#downloads

In MySQL 5.7 we are planning to deprecate the syntax:

EXPLAIN PARTITIONS <insert query here>
EXPLAIN EXTENDED <insert query here>

.. and enable these two options by default.

The rationale is that:

• Simple and consistent is always better. EXPLAIN FORMAT=JSON already behaves like these two flags are enabled, and if you have a partitioned table for example, it is unlikely that you would not want the PARTITIONS option. Having to remember two more flags makes the product harder to use.

• The optimizer team has been busy refactoring and improving code quality. These two flags are supported by many if-statements, increasing complexity by more than we would like.

The intended deprecation plan is to automatically turn both flags on in MySQL 5.7 …