In the previous post for this ongoing “EXPLAIN FORMAT=JSON is Cool!” series, we discussed covered indexes and how the 

used_columns

  array can help to choose them wisely. There is one more type of multiple-column indexes: composite indexes. Composite indexes are just indexes on multiple columns. Covered indexes are a subgroup of the larger set “composite indexes.” In this post we’ll discuss how “used_key_parts” can help show …

In November we held our first MySQL 5.8 planning session in London. On behalf of the MySQL team, I would like to thank you for your feature requests and suggestions. We reviewed over 150 pieces of feedback in total, and are looking forward to prioritizing a number of suggestions:

In MySQL 5.8, we are planning to make two important changes to modernize our code base.…

Percona is glad to announce the release of Percona XtraBackup 2.3.3 on December 17th, 2015. Downloads are available from our download site or Percona Software Repositories.

Percona XtraBackup enables MySQL backups without blocking user queries, making it ideal for companies with large data sets and mission-critical applications that cannot tolerate long periods of downtime. Offered free as an open source solution, Percona XtraBackup drives down backup costs while providing unique features for MySQL backups.

…

Knowing which privileges a given account has is easy – just issue SHOW GRANTS FOR user@host.  But what about when you need visibility into privileges from the other direction – which accounts can access specific data?  If you’re a DBA – or perform DBA duties, regardless of your title – you may have been asked this question.  It’s an important question to ask in an audit or compliance review – but it can be a difficult question to answer.    This post will walk through how to assess this, but if you’re impatient and need answers to this question immediately, jump to the end – there’s a simple shortcut.

Things to consider

There are a few things you’ll want to consider about the implementation of the MySQL privilege system as you try to sort out who has access to certain data.

Access type

MySQL can restrict privileges based on operations – somebody who has …

We work on data recoveries quite often. In many cases, we recover table structures from the .frm files because there was no backup available. There is already a great blog post by my colleague Miguel Ángel Nieto about how we can recover structures from .frm files using MySQL utilities.

This works pretty well and we prefer to run mysqlfrm with the “–server” option to get all possible information from a .frm file. However, this option expects that MySQL is up and running so that mysqlfrm can spawn a new MySQL instance, and run the structure recovery there.

Recently I came across a tool that makes this job easier. The name of tool is …

At Yahoo, we manage a massive number of MySQL databases spread across multiple data centers.

We have thousands of databases and each database has many partitioned tables. In order to efficiently create and maintain partitions we developed a partition manager which automatically manages these for you with minimal pre configuration.

Today, we’re releasing MySQL Partition Manager. You can check out the code on GitHub.

We’re looking forward to interacting with the MySQL community and continue developing new features.

- MySQL Database Engineering Team, Yahoo

At Yahoo, we manage a massive number of MySQL databases spread across multiple data centers.

We have thousands of databases and each database has many partitioned tables. In order to efficiently create and maintain partitions we developed a partition manager which automatically manages these for you with minimal pre configuration.

Today, we’re releasing MySQL Partition Manager. You can check out the code on GitHub.

We’re looking forward to interacting with the MySQL community and continue developing new features.

- MySQL Database Engineering Team, Yahoo

The MySQL developer tools team announces 6.3.6 as our GA release for MySQL Workbench 6.3.

For the full list of changes in this revision, visit
http://dev.mysql.com/doc/relnotes/workbench/en/changes-6-3.html

For discussion, join the MySQL Workbench Forums:
http://forums.mysql.com/list.php?152

Download MySQL Workbench 6.3.6 GA now, for Windows, Mac OS X 10.9+,
Oracle Linux 6 and 7, Fedora 22 and Fedora 23, Ubuntu 14.04 and
Ubuntu 15.10 or sources, from:
http://dev.mysql.com/downloads/tools/workbench/

Enjoy!

A WordCamp US this year, I spoke about the Trojan Emoji security bug, which we fixed in WordPress 4.1.2.

In particular, I went through how we came to wrap our head around the bug, and then write a solution that worked for every WordPress site.

If you have used SQL a bit, you are certainly familiar with so-called set functions or aggregate functions COUNT, SUM, AVG, described in the manual. For example, let’s say that I am the owner of a shop and I keep track of daily sales in this table:

create table sales (month int, day int, amount int);

The first column is the number of the month, between 1 and 12, the second column is the number of the day in the month, between 1 and 31, and the third column is how much we sold on that date.…