Back in October I have write about possible ways of running multiple MySQL instances on the same hardware. As the months passing by, the project of splitting our database schemas into standalone instances is closing in, so I started to check the different ways.

EDIT: This post is outdated, here is the follow up.

I started with docker, because we’ll use containers anyway with the applications, and I think it is a good idea to minimise the diversity of an infrastructure. I used the docker’s “official” Percona image (it is official by Docker not by Percona!) which is easy to use, and flexible enough. (https://hub.docker.com/_/percona/) This image supports using custom config files, you can mount your …

Over several previous blog posts, we’ve already discussed what information the 

EXPLAIN FORMAT=JSON

 output provides for some subqueries. You can review those discussions here, here and here. EXPLAIN FORMAT=JSON shows many details that you can’t get with other commands. Let’s now finish this topic and discuss the output for the rest of the subquery types.

…

Reminder: MTS = Multi-Threaded Slave.

Update 2017-04-17: since the publication of this post, many things happened:

the procedure for fixing a crashed slave has been automated (Bug#77496) Bug#80103 as been closed at the same time as Bug#77496 but I still think there are unfixed things, see Bug#81840

End of update 2017-04-17.

I will be talking about parallel replication at FOSDEM in Brussel on

We’d like to thank everybody for joining us on January 7th for our “Tired of MySQL Making You Wait?” webinar with Percona’s Alexander Rubin, Principal Consultant and SolarWinds’ Janis Griffin, Database Evangelist.

Too often developers and DBAs struggle to pinpoint the root cause of performance issues and then spend too much time in trying to fix them. In the webinar, we discussed how you can significantly increase the performance of your applications while also reducing database response time.

You can find an archived version of the webinar here.

Below are the questions that were asked during the webinar, with responses from Alex and Janis. If you need further clarification, please respond in the comments.

Thanks again, and we look forward to you joining us at our next webinar (with Percona CEO Peter …

I saw an interesting post about the ability of installing MySQL 5.7 without changing existing tools and procedures. The post is a plea to make MySQL installation frictionless.

That post was followed by a conversation on Twitter, where the recent security enhancements are blamed for getting in the way of existing practices and need a rewrite of installation tools.

I know the problem very well, as I have faced the installation change in MySQL Sandbox. SO I can sympathize with the ones who have to change deployment tools that rely on mysql_install_db, which was a Perl script up to version 5.6, then it was replaced with a C++ program in 5.7 and deprecated in the same version.

It occurred to me that, in order to keep the …

The “CAP theorem” is often presented as something deep and hard to understand, and then discussed in confusing terms, to make sure it is hard to understand.  Really, it’s almost common sense – eg, if you have a partition, you have to give up availability or consistency.  Anyone familiar with, eg, drbd/split-brain/STONITH knows all about this.

I was reading a bit about it (again), and I use the sneer quotes on “theorem” because I think that the “proof” is really just adding some mathematical terms to the mix and restating it – QED.  (If this is considered the proof – “Brewer’s Conjecture and the Feasibility of Consistent, Available, Partition-Tolerant Web Services” .)  “Conjecture” doesn’t seem right either.  Maybe CAP observation?

It’s refreshing to …

With MySQL 5.7, our goal is to be secure by default. This means that without having to change configuration settings or perform any additional steps, your fresh installation should be safe for production use.

As part of this security initiative, MySQL 5.7 shipped with a new feature where user accounts will be disabled if the password has not been changed in a number of days.…

We have discussed about the conceptual data model, logical data model, normalization and denormalization techniques and we discussed about installing and running up with MySQL community server.  What will be next? Once we build the data model and decided the database server, the next process will be start developing the physical database. What is needed to develop physical database? We need a common language to communicate with both the developer and database server. Here, comes the structure query language. So in this post we are going to see about the …

Earlier today advisories were sent out regarding OpenSSH versions 5.4 through 7.1., informing users about a security bug in the software. In essence, the advisory instructed people to add the  

UseRoaming no

 option to their ssh_config file, with a promise for further information to be made available shortly.

Add undocumented "UseRoaming no" to ssh_config or use "-oUseRoaming=no" to prevent upcoming #openssh client bug CVE-2016-0777. More later.

— markus (@msfriedl) January 14, 2016

The post on the security issue at OpenBSD Journal can be seen here: http://undeadly.org/cgi?action=article&sid=20160114142733 …

Hi all, it is time again to do another preview release of MySQL Group Replication, the plugin that brings multi-master update everywhere to MySQL, like we described in Hello World post.

We are very proud to do the sixth preview release of MySQL Group Replication, version 0.7.0 based on MySQL Server 5.7.10, which introduces new exciting features, please enjoy the highlights!…