News

In MariaDB master/slave replication there is a feature called attribute promotion/demotion.

Simply put, it is about how the slave behaves or should behave if the master and slave have different column definitions or even a different number of columns or a different sequence of columns.

Use case of the customer

This week we discussed with a customer the case of how he could perform a rolling schema upgrade (RSU) in a Galera cluster.

With previous schema changes he has always had problems, which has led to a …

FromDual has the pleasure to announce the release of the new version 2.3.2 of its popular Backup and Recovery Manager for MariaDB and MySQL (brman).

The new FromDual Backup and Recovery Manager can be downloaded from here. The FromDual Repositories were updated. How to install and use the Backup and Recovery Manager is described in FromDual Backup and Recovery Manager (brman) installation guide.

In the inconceivable case that you find a bug in the FromDual Backup and Recovery Manager please send us an …

In our MariaDB advanced training courses, which we hold approximately every two months, we use machines that are directly exposed to the Internet with a public IP address. Warning: You should NEVER expose a database directly to the Internet without protection! Typically, it takes less than 72 hours (3 days) before we are exposed to the first external access attempts.

This looks something like this in the MariaDB error log:

[Warning] Aborted connection 22939 to db: 'unconnected' user: 'unauthenticated' host: …

Since 10.11 it would be good to use –dump-history if MariaDB System-Versioned Tables are used!

Recently I had the opportunity to have a lot of Linux systems (VMs with Rocky Linux 9) from one of our regular Galera Cluster trainings all to myself for a week. And MariaDB 11.4.4 with Galera Cluster was already installed on the machines.

Since I had long wanted to try out how a Galera Cluster behaves with an increasing number of nodes, now was the opportunity to try it out.

The following questions were to be answered:

• How does the throughput of a Galera cluster behave depending on the number of Galera …

We have improved our model (see v2) so the results are a bit better/more accurate now.

For usage see ./fromdual_llm_v2.php --help

Artificial intelligence (AI) and vector databases are on everyone’s lips these days. Since MariaDB will soon be coming onto the market with vector database functionality, as a database consultant I thought it was about time I got to grips with the subject so that I have at least a hint of what it’s all about…

Since I’m not so much of a theoretician but rather like to do something practical, I’ve built a small “AI” prototype that anyone can build very quickly and …

FromDual has the pleasure to announce the release of the new version 2.3.1 of its popular Backup and Recovery Manager for MariaDB and MySQL (brman).

The new FromDual Backup and Recovery Manager can be downloaded from here. The FromDual Repositories were updated. How to install and use the Backup and Recovery Manager is described in FromDual Backup and Recovery Manager (brman) installation guide.

In the inconceivable case that you find a bug in the FromDual Backup and Recovery Manager please report it to the …

What is it about?

When describing backup and restore scenarios, a full backup and a full restore of the database instance (mariadbd/mysqld) are usually assumed. This means that the entire database instance, including all databases (schemas), is backed up and restored.

In practice, however, the situation is often different: An entire database instance is not to be restored, but only individual databases or even individual tables, because only these have broken.

In many cases, this can be done quite easily …

FromDual has the pleasure to announce the release of the new version 2.3.0 of its popular Backup and Recovery Manager for MariaDB and MySQL (brman).

The new FromDual Backup and Recovery Manager can be downloaded from here. The FromDual Repositories were updated. How to install and use the Backup and Recovery Manager is described in FromDual Backup and Recovery Manager (brman) installation guide.

In the inconceivable case that you find a bug in the FromDual Backup and Recovery Manager please report it to the …

One feature that really excited me in the new MariaDB 11.4 LTS release is the shrinking of the system tablespace (ibdata1). I have been eagerly waiting for this feature since around 2006 and now it has finally arrived with MariaDB 11.4. Actually, this feature has been available since MariaDB 11.2 IR (June 2023).

Unfortunately, the announcement of this feature came a little too short. In the MariaDB release notes it says succinctly:

https://jira.mariadb.org/browse/MDEV-34412

Hi dcz01

No it is not solved… It is closed and “not a bug”… I try to intervene

Regards, Oli

Hello dcz01

I would say, this is probably a bug. I can reproduce it on my system (MySQL 5.7 Master and MariaDB 10.6 Galera Cluster).

Please contact your MariaDB support contact… If you need assistance we are happy to sell you our remote-DBA services…

Regards, Oli

On this page we have summarised information about downgrading a MariaDB/MySQL database. We do not cover migrating from MySQL to MariaDB or vice versa. For migrations (sidegrade) please look here: MySQL - MariaDB migration and here: Migration between MySQL/Percona Server and MariaDB.

The downgrade process tends to be neglected because nobody really wants to do it. So we are in swampy territory here. Unforeseen situations can occur very easily and good preparation is essential.

I can think of the following …

FromDual is pleased to announce the release of the new version 1.2.2 of the popular FromDual Ops Center focmm, a Graphical User Interface (GUI) for MariaDB, MySQL and compatible databases.

The FromDual Ops Center for MariaDB and MySQL (focmm) helps DBAs and system administrators to better manage their MariaDB and MySQL databases and Galera Cluster farms. Ops Center makes life easier for DBAs and Admins!

The main purpose of the Ops Center is to help you with your daily MariaDB and MySQL operations. More …

• Ops Center 1.2.2 Release Notes: FromDual Ops Center 1.2.2 for MariaDB, MySQL and compatible databases has been released (2024-04-25)
• Ops Center 1.2.1 Release Notes: FromDual Ops Center 1.2.1 for MariaDB, MySQL and compatible databases has been released (2023-02-07)
• Ops Center 1.2.0 Release Notes: FromDual Ops Center 1.2.0 for MariaDB, MySQL and compatible databases has been released (2023-01-17)
• Ops Center 1.1.0 Release Notes: FromDual Ops Center for MariaDB, MySQL and compatible databases 1.1.0 has been …

Table of contents

• Review
• One month later
• Size of the tables
• Process list
• Global variables
• Metadata Lock and InnoDB Transaction Lock
• Global status

Review

After we introduced dbstat for MariaDB (and MySQL) a good 5 weeks ago, we naturally also rolled it out on our systems to test the behaviour in daily use (eat your own dog food).

This went quite well until we came up with the idea of activating dbstat on the passive dbstat node on our MariaDB active/passive master/master replication cluster (a similar …

Due to an application error, our replication stopped for 5 days (over Easter). After the problem was solved, the replication was supposed to catch up, which turned out to be very slow. All the usual tricks (innodb_flush_log_at_trx_commit, sync_binlog, etc.) had already been exhausted. So we tried our hand at parallel replication of the MariaDB server.

Parallel replication is deactivated by default:

SQL> SHOW GLOBAL VARIABLES LIKE '%parallel%';
+-------------------------------+------------+
| …

Recently I had to test a new MariaDB feature that was developed at our request (MDEV-33782). To test this feature I had to build the MariaDB server myself from source, which I have not done for a long time. So a new challenge, especially with CMake…

I followed the MariaDB documentation Get, Build and Test Latest MariaDB the Lazy Way to build the server.

On Ubuntu 22.04 it did not work for me, for reasons unknown to me. So I cloned an Ubuntu 23.04 (Lunar Lobster) LXC container and built the MariaDB …