MySQL Tech-Feed (en)

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, Release Date: 25 April 2024
• Ops Center 1.2.1 Release Notes, Release Date: 7 Februray 2023
• Ops Center 1.2.0 Release Notes, Release Date: 17 January 2023
• Ops Center 1.1.0 Release Notes, Release Date: 7 May 2021
• Ops Center 1.0.0 Release Notes, Release Date: 7 May 2020
• Ops Center 0.9.3 Release Notes, Release Date: 18 February 2020
• Ops Center 0.9.2 Release Notes, Release Date: 13 August 2019
• Ops Center 0.9.1 Release Notes, Release Date: 7 May 2019
• Ops Center 0.9.0 Release Notes, …

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 …

Table of contents

• Overview
• Preparations
• Activate MaxScale configuration synchronisation
• Change MaxScale parameters
• Add new slave and make MaxScale known
• Remove old slave and make MaxScale known
• How is the configuration synchronised?
• What happens in the event of a conflict?
• Tests
• Deactivating MaxScale configuration synchronisation again
• Literature/sources

Overview

A feature that I recently discovered while browsing is the MaxScale configuration synchronisation functionality.

This is not primarily about a …

Table of contents

• Overview
• Preparation of the shards (MariaDB database instances)
  • Create test data
  • Creating roles and users
  • MaxScale Monitor User
  • MaxScale Admin User
  • Create application role and accounts
  • Proxy protocol
• MaxScale SchemaRouter configuration
• Starting and stopping the MaxScale Load Balancer
• Application tests
  • Simple application tests
  • New command show shards
  • More general test
  • Less simple tests
  • More complex application tests
  • Cross-shard tests
• Operation of a MaxScale sharding system …

Table of contents

• Functionality of dbstat
• How does dbstat work
• How to install dbstat
• Query dbstat
  • table_size
  • processlist
  • trx_and_lck
  • metadata_lock
  • global_variables
  • global_status
• Testing
• Sources

An idea that I have been thinking about for a long time and have now, thanks to a customer, finally tackled is dbstat for MariaDB/MySQL. The idea is based on sar/sysstat by Sebastien Godard:

sar - Collect, report, or save system activity information.

and Oracle Statspack:

Statspack is a performance tuning …

• MyEnv 3.0.0 Release Notes, Release Date: 23 March 2026
• MyEnv 2.1.1 Release Notes, Release Date: 12 December 2025
• MyEnv 2.1.0 Release Notes, Release Date: 28 February 2024
• MyEnv 2.0.3 Release Notes, Release Date: 2 July 2021
• MyEnv 2.0.2 Release Notes, Release Date: 17 January 2019
• MyEnv 2.0.1 Release Notes, Release Date: 3 October 2018
• MyEnv 2.0.0 Release Notes, Release Date: 15 March 2018
• MyEnv 1.3.1 Release Notes, Release Date: 3 August 2016
• MyEnv 1.3.0 Release Notes, Release Date: 31 January 2016
• MyEnv …

The design of a data warehouse differs from relational design. Data warehouses are often designed according to the concept of the star schema.

When building a data warehouse, you usually put the cart before the horse:

• What questions should my data warehouse be able to answer?
• How do I have to design my model so that my questions can be answered easily?
• Where do I get the data to populate the model?
• How do I fill my model with the data?

For training purposes, we have investigated an issue that arises from …