Before I upgrade MySQL to the latest and greatest version, one of the first things that I do is export the user and grant information. In the past, I would keep all of my user information (user name, password, grants) in a text file, with the SQL for each user/grant ready to be executed on the upgraded server. I did use my own form of “mental encryption” for my passwords, so the passwords weren’t in plain English. But then I would have to decode my passwords each time before I executed the SQL statements.

When I upgrade, I usually like to dump all of the data and import it into the new version, so I have a fresh copy of the database. The MySQL server that I have is for my personal use and the data size is relatively small, so for my case it doesn’t take long to import the data.

But there were times when I would add a user in the MySQL database and forget to add it to my text file. Then, when it came time to upgrade and I …

If you aren’t familiar with MySQL replication, “Replication enables data from one MySQL database server (the master) to be replicated to one or more MySQL database servers (the slaves). Replication is asynchronous by default – slaves need not to connected permanently to receive updates from the master. This means that updates can occur over long-distance connections and even over temporary or intermittent connections such as a dial-up service. Depending on the configuration, you can replicate all databases, selected databases, or even selected tables within a database.” (From: http://dev.mysql.com/doc/refman/5.5/en/replication.html).

I use MySQL replication on my home office server. I don’t really have much data to store, but it is nice to have several replicated slaves for backup purposes and also for testing new replication features of MySQL. I …

The WordPress.com stats helper monkeys prepared a 2012 annual report for this blog. Here’s an excerpt: 4,329 films were submitted to the 2012 Cannes Film Festival. This blog had 21,000 views in 2012. If each view were a film, this blog would power 5 Film Festivals Click here to see the complete report.

This is just a reminder: Call for papers for MySQL & Friends devroom at FOSDEM 2013 is open until December 21st, which is this Friday. Please hurry up and submit your proposal. Possible topics include everything related to MySQL.

MariaDB 10.0 has got another new feature: Sanja Byelkin has pushed EXISTS-to-IN rewrite feature. It is an optimization targeted at EXISTS subqueries. The idea behind it is simple. EXISTS subqueries often have form:

EXISTS (SELECT …  FROM … WHERE outer_col=inner_col AND inner_where)

where outer_col=inner_col is the only place where the subquery has references to outside. In this case, the subquery can be converted into an uncorrelated IN:

outer_col IN (SELECT inner_col FROM … WHERE inner_where)

The conversion opens new opportunities for the optimizer. Correlated EXISTS subquery has only one execution strategy. Uncorrelated IN subquery has two:

1. re-run the subquery every time the subquery is evaluated (the same as in EXISTS)
2. Materialize the subquery output …

16 Table Join Benchmarks were ran at Amazon Web Services.

Results available at www.paralleluniverse-inc.com/benchmarks.shtml .

This post is the second in a series that I will be doing on MySQL Workbench Utilities – Administer MySQL with Python Scripts. You may want to read the first half of this post to understand how MySQL Workbench Utilities work and how you access the scripts. These scripts were written by Chuck Bell (a MySQL employee) and are available as stand-alone scripts (see Chuck’s …

“Some people even think that “Hadoop” and “Big Data” are synonymous (though this is an over-characterization). Unfortunately, Hadoop was designed based on a paper by Google in 2004 which was focused on use cases involving unstructured data (e.g. extracting words and phrases from Webpages in order to create Google’s Web index). Since it was not [...]

You may have already seen the announcement MariaDB Foundation to Safeguard Leading Open Source Database. We at Open Query wholeheartedly support this (r)evolution of the MySQL ecosystem, which appears to be increasingly necessary as Oracle Corp is seriously dropping the ball with security updates and actually just general development and innovation. Oracle has actually done some very good work, I happily acknowledge that – but security issues are critical, having crashing bugs and incorrect query results in a .28 of a GA release is uncool, and not incorporating awesome development efforts by the community is just astonishing.

MariaDB is where the Sphinx fulltext …

Important Security Fix for a Buffer Overflow Bug: MariaDB 5.5.28a, 5.3.11, 5.2.13 and 5.1.66 include a fix for CVE-2012-5579, a vulnerability that allowed an authenticated user to crash MariaDB server or to execute arbitrary code with the privileges of the mysqld process. This is a serious security issue. We recommend upgrading from older versions as soon as possible.

MariaDB 5.5.28a, 5.3.11, 5.2.13 and 5.1.66 (GA) binaries, packages, and source tarballs are now available for download from http://downloads.mariadb.org. So you can upgrade within your own major series.

Note that while this fix has just been published, some other vulnerabilities have been noted over the weekend also. Below a summary of these other CVEs as documented by Red Hat Security Response Team, with annotations by Sergei Gulubchik who is the Security Coordinator for MariaDB.

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