replicate_rewrite_db as a system variable in MariaDB

MariaDB 10.11.0, our latest preview release, features quite a number of improvements. The one we’ll talk about here is replicate-rewrite-db. This option has become a system variable from 10.11.0 based on MDEV-15530. Before this version it was just an option used by the mariadbd and mariadb-binlog binaries. There have been no behaviour changes with the option; it has simply become a dynamic variable.

How to try out this feature

The fastest way is to take MariaDB 10.11 for a spin in docker / podman (consult the blog mariadb-replication-using-containers) with the following commands:

To start a primary 10.11.0 MariaDB container, clone the directory, navigate to the cloned directory and run the following command:

docker run -d –rm –name mariadb-primary \
-v $PWD/config-files/primarycnf:/etc/mysql/conf.d:z \
-v $PWD/primaryinit:/docker-entrypoint-initdb.d:z \
-v $PWD/log-files-primary:/var/lib/mysql \

To start the replica/secondary run the command to start the mariadbd process as well as specify the replicate-rewrite-db option on the command line:

docker run -d –rm –name mariadb-secondary-1 \
-v $PWD/config-files/secondary-1:/etc/mysql/conf.d:z \
-v $PWD/secondaryinit:/docker-entrypoint-initdb.d:z \
-v $PWD/log-files-secondary-1:/var/lib/mysql \
-e MARIADB_ALLOW_EMPTY_ROOT_PASSWORD=True \ –replicate-rewrite-db=’db1->db2′

Besides specifying the option as a command line argument, you can use a configuration file.

CfP for the MariaDB, MySQL and Friends devroom FOSDEM 2023 now open

FOSDEM 2023 is happily once again going to be an in-person event, and MariaDB will be participating as part of the MariaDB, MySQL and Friends devroom. The Call for Papers is now open.

FOSDEM 2023 will take place on Sat 4 to Sun 5 February 2023 at the ULB Solbosch Campus, Brussels, Belgium.

There are some changes in the organization to previous years. MySQL and MariaDB will each be responsible for its own track, so we will divide the devroom in two sub-tracks.

For the convenience of the speakers and participants, we will not mix the two sub-tracks, and you will have the possibility to follow either track you are interested in, or of course both. …

MariaDB 10.9.4, 10.8.6, 10.7.7, 10.6.11, 10.5.18, 10.4.27 and 10.3.37 now available

The MariaDB Foundation is pleased to announce the availability of MariaDB 10.9.4, MariaDB 10.8.6 and MariaDB 10.7.7, the latest Generally Available releases in their respective short-term series (maintained for one year from their first GA release dates), as well as MariaDB 10.6.11, MariaDB 10.5.18, MariaDB 10.4.27 and MariaDB 10.3.37, the latest stable release in their respective long-term series (maintained for five years).

See the release notes and changelogs for details.

Download MariaDB 10.9.4

Release Notes Changelog What is MariaDB 10.9?

MariaDB metrics errors – a post-mortem

I’m going to start this blog post by saying that I made a mistake, a mistake that means all of the metrics blog posts so far have been made with erroneous data. As part of our openness value I will give a post-mortem of the issue here.

Metrics generation

Before we look into what went wrong, I first need to give a bit of background. The commit metrics are generated using a tool called “gitdm”, this is a “Git Data Miner” that was designed to generate commit statistics for the Linux Kernel. Our fork of this is in the metrics repository which includes some customisations that fit MariaDB Server’s needs better.

This one trick can make MariaDB 30x faster!

Yes, it is a bit of a click-bait title, but in this case running one SQL command did improve a community user’s performance by that much. It could help you too.

The story

A community user posted in a couple of places that when migrating a large WordPress installation to MariaDB that they were seeing a certain query performing terribly. The query was taking 1.5 seconds to execute and it was clear from the explain plan that the optimizer was not making an ideal decision about the join order.

The query was generated by WordPress so it would not be easy to force an index, or rewrite the query.


MariaDB 10.11.0, our latest preview release, features quite a number of improvements. The one we’ll talk about today is GRANT … TO PUBLIC.


MariaDB has quite a complex privilege system. Most of it is based on the SQL Standard spec; however we do have some specific MariaDB extensions. GRANT … TO PUBLIC (MDEV-5215) is a standard feature that is now available as a preview in MariaDB 10.11.0. It is related to ROLES and DEFAULT ROLE, but it covers a different use case.

ROLES are effectively “privilege packages” that you can enable and disable as a user.

Contribution Statistics September 2022

Last month we provided contributor statistics for the last few years. We have had some fantastic feedback from this so today we are presenting you with another drop of contributor statistics for the last month. Normally we would be doing these quarterly but there are so many extra things to report that we decided to do a bonus one now.

Some key things have happened in the last month which affect the data, the first is that MariaDB 10.11 has had a preview release. Which means there has been a flurry of activity around this.

MariaDB Server Fest 17 Nov 2022

The MariaDB Foundation will be hosting a Server Fest on Thursday 17 November 2022. This time it’ll be a hybrid event, harnessing the energy that comes from many of the participants being present in person.

To encourage interaction, the event will be streamed live, but will not immediately be made available online, so don’t miss out on this opportunity to interact with the speakers and MariaDB members in person!

The keynote speaker will be Wikimedia Foundation’s Manuel Arostegui. The schedule and further details will be announced soon.

We start at 14:00 Paris time (CET) – 8:00am New York, 20:00 Beijing.