Shinguz's blog

Due to a strong customer demand FromDual offers 2018 two extra MySQL/MariaDB trainings with its Training partner The Linuxhotel in Essen (Germany). Those trainings are in English.

Coming soon…

FromDual as a neutral and vendor independent database service company also provides various services for the MariaDB database.

MySQL has introduced the PERFORMANCE_SCHEMA (P_S) in MySQL 5.5 and made it really usable in MySQL 5.6 and added some enhancements in MySQL 5.7 and 8.0.

The Chemnitz Linux Days 2018 in Chemnitz (Germany) 10/11 March 2018 are over for more than a week now and IMHO it was a huge success.

FromDual has the pleasure to announce the release of the new version 2.0.0 of its popular MySQL, Galera Cluster and MariaDB multi-instance environment MyEnv.

Due to the increasing demand FromDual has developed an Advanced MySQL Enterprise Training for DBAs and DevOps. After testing this training extensively with some selected customers last year we offer this MySQL Enterprise Training in 2018 for a broader audience.

Yesterday MySQL 8.0.4-rc came out. The Release Notes are quite long.
But caution: Do a BACKUP before upgrading…

FromDual offers short term a Percona XtraDB Cluster and MySQL Galera Cluster training (2 days) in English.

End of February, from February 26 to March 2 (5 days), FromDual offers an additional training for DBAs and DevOps: our most visited Advanced MySQL and MariaDB training.

As in every quarter of the year Oracle has released yesterday its recommendation for the MySQL security updates. This is called, in Oracle terminology, Critical Patch Update (CPU) Advisory.

If you are already familiar with MySQL and you are challenged to operate a serious MySQL Enterprise infrastructure this training is the right one for you.

Today we had to investigate in a very strange behaviour of IST and SST on a MariaDB Galera Cluster.

The Docker version of the distributions are often quite old. On Ubuntu 16.04 for example:

Important: FromDual does NOT recommend to use an automated VIP failover technology as described below for a MariaDB/MySQL Master/Master Replication. In such a topology we recommend a manual VIP failover with prepared scripts!

There are some pretty sophisticated Load Balancers for Galera Clusters setups out in the market (ProxySQL, MaxScale, HAproxy, …). They have many different exotic features. You can nearly do everything with them. But this comes at the cost of complexity. Non of them is simple any more.

There are 2 different ways to solve this task.

The first way is by enabling the variable log_queries_not_using_indexes (MariaDB/MySQL). This can be done eigther online:

The query is so evil/slow because it does a Full Index Scan (FIS). Other call this operation also a Index Fast Full Scan (IFFS). This is much too much work for the result wanted (the value of the AUTO_INCREMENT column).

Recently I switched on the MariaDB slow query logging flag log_queries_not_using_indexes just for curiosity on one of our customers systems:

We have sometimes discussions with our customers whether to store LOBs (Large Objects) in the database or not. To not rephrase the arguments again and again I have summarized them in the following lines.