Michael Widenius

Why 11.0 and what's new

The MariaDB optimizer has its roots in the original MySQL optimizer. Being a long standing project, it has inherited a number of quirks and features that -at the time of coding- made sense. The datasets had different sizes 10-20 years ago and the cost model is not always accurate for current workloads.

Thus, there is now an ongoing effort to significantly improve the calculations that the MariaDB Optimizer is doing. With the addition of JSON Histograms, the range optimizer is one of the most impacted modules. The end goal of this effort is to provide the user with a better query optimizer, but also put the user in control and allow the user to tweak many more parameters than were previously available. In this talk I will go through the major changes that are upcoming in MariaDB, changes that could impact query performance (for the better) and also raise awareness about which parameters have the highest impact on query optimizer performance.

As was announced in December 2021 https://mariadb.org/new-innovation-release-model/, MariaDB Server now has a new release model, with more frequent major releases. MariaDB Server 10.7 is the first release following this model.

Some of these releases will have 1 year support cycles, while others will be supported long term just like before. In this talk, I will present the pros and cons of this new release model, what it means for the MariaDB Server community, its users and also its developers. This will also give the community a chance to better understand the changes and give us feedback and ultimately ensure MariaDB Server properly serves its purpose of being a true Open Source Database.

Crash safety is one of the requirements of modern databases. Although DML is crash safe (depending on storage engine), DDL is still problematic. MariaDB 10.6 will implement atomic DDL. Currently RENAME and DROP are fully supported for all database objects and the goal is to implement all remaining operations. This talk will go into the technical details of the atomic DDL implementation, explaining how it provides crash safety.

This talk will present a proper procedure of migrating applications from proprietary database systems (such as Oracle or SQL Server) to MariaDB. The talk will give an overview of the steps required to successfully perform a full migration. built from the experience of migrating DBS Bank's core infrastructure from Oracle to MariaDB.