Today’s blog post is related again to MySQL Group Replication.

By default MySQL Group Replication runs in Single-Primary mode. And it’s the best option and the option you should use.

But sometimes it might happen that in very specific cases you would like to run you MGR Cluster in Multi-Primary mode: writing simultaneously on all the nodes member of the Group.

It’s of course feasible but you need to make some extra verification as not all workload are compatible with this behavior of the cluster.

Requirements

The requirements are the same as those for using MGR in Single-Primary mode:

• InnoDB Storage Engine
• Primary Keys
• IPv4 Network
• Binary Log Active
• Slave Updates Logged
• Binary …

This post discusses enabling and disabling jemalloc on Percona Server for MySQL.

The benefits of jemalloc versus glibc for use with MySQL have been widely discussed. With jemalloc (along with Transparent Huge Pages disabled) you have less memory fragmentation, and thus more efficient resource management of the available server memory.

For standard installations of Percona Server 5.6+ (releases starting with 5.6.19-67.0), the only thing needed to …

Hi all,

Fosdem’s organization relocated the MySQL & Friends Devroom from H.1308 to H.1309 (Van Rijn).

It’s the same building, just the door next to it.

MySQL will also have a stand in the H building. Don’t hesitate to visit it (I’ve heard there will be some Sakila Dolphins !)

This blog provides a query language type overview.

The idea for this blog originated from some customers asking me questions. When working in a particular field, you often a dedicated vocabulary that makes sense to your peers. It often includes phrases and abbreviations because it’s efficient. It’s no different in the database world. Much of this language might make sense to DBA’s, but it might sound like “voodoo” to people not used to it. The overview below covers the basic types of query languages inside SQL. I hope it clarifies what they mean, how they’re used and how you should interpret them.

DDL (Data Definition Language)

A database schema is a visualization of information. It contains the data structure separated by tables structures, views and anything that contains structure …

Oracle’s  MySQL Community Team is organizing a pre-Fosdem MySQL Day on Friday 3rd February 2017.

The event is free (like in beer) for all participants but as seating is limited, registration is required.

Come to meet MySQL engineers and listen to them talking about new MySQL 8.0’s features. Some of Percona’s experienced staff will also deliver some talks on troubleshooting, architecture, …

And finally, Booking.com will also share their user experience with the audience.

What else to start the Fosdem Week-end in the best way ?

Agenda and registration can be found on lefred’s blog !

This year, I’ve the honor to organize just before the FOSDEM MySQL & Friends Devroom an extra pre-FOSDEM MySQL Day. This MySQL Day will take place the Friday just before FOSDEM’s week-end.

During that day, we will highlight MySQL 8.0 new features but not only.

Oracle’s MySQL Community Team is sponsoring this event. Seating is limited, so please register.

The event is free and the location is the same as the very popular MySQL & Friends Community Dinner.

You can register now on eventbrite.

This is the agenda:

Welcome to another post in the series of Percona Live featured tutorial speakers blogs! In these blogs, we’ll highlight some of the tutorial speakers that will be at this year’s Percona Live conference. We’ll also discuss how these tutorials can help you improve your database environment. Make sure to read to the end to get a special Percona Live 2017 registration bonus!

In this Percona Live featured tutorial, we’ll meet Øystein Grøvlen, Senior Principal Software Engineer at Oracle. His tutorial is on How to Analyze and Tune MySQL Queries for Better Performance. SQL query …

In a previous article, Ovais demonstrated how a DDL can render a table blocked from new queries. In another article, Valerii introduced performance_schema.metadata_locks, which is available in MySQL 5.7 and exposes metadata lock details. Given this information, here’s a quick way to troubleshoot metadata locks by creating a stored procedure that can:

• Find out which thread(s) have the metadata lock
• Determine which thread has been waiting for it the longest
• Find other threads waiting for the metadata lock

Setting up …

This year, the MySQL & Friends Devroom will be held on Saturday 4th February 2017.

After having received a lot of submission (the highest amount ever!), with MySQL Community Team, we decided to organize and extra MySQL day that will take place at ICAB Incubator, 4 Rue des Pères Blancs in Brussels (same location as the MySQL Community Dinner). More to come on this day in a future blog post.

So back to the MySQL & Friends Devroom, the Committee high rated the following talks:

In this blog post, we’ll find out how to use Percona XtraBackup on a MySQL instance with a large number of tables.

As of Percona Xtrabackup 2.4.5, you are required to have enough open files to open every single InnoDB tablespace in the instance you’re trying to back up. So if you’re running innodb_file_per_table=1, and have a large number of tables, you’re very likely to see Percona XtraBackup fail with the following error message:

InnoDB: Operating system error number 24 in a file operation.
InnoDB: Error number 24 means 'Too many open files'
InnoDB: Some operating system error numbers are described at http://dev.mysql.com/doc/refman/5.7/en/operating-system-error-codes.html
InnoDB: File ./sbtest/sbtest132841.ibd: 'open' returned OS error 124. Cannot continue operation
InnoDB: Cannot …