We usually receive and see some questions regarding the charset levels in MySQL, especially after the deprecation of utf8mb3 and the new default uf8mb4. If you understand how the charset works on MySQL but have some questions regarding this change, please check out Migrating to utf8mb4: Things to Consider by Sveta Smirnova.Some of the questions […]

This blog was originally published in February 2019 and was updated in September 2023.

Web applications rely on databases to run the internet, powering everything from e-commerce platforms to social media networks to streaming services. MySQL is one of the most popular database management systems, playing a pivotal role in the functionality and performance of web applications.

In today’s blog, I’ll take a look at MySQL collation and charset settings to shed light on how they impact the performance of web applications and how to use them to effectively communicate with your users.

Understanding Character Sets and Encoding in MySQL

Character sets and encoding in MySQL play a vital role in how data is stored and retrieved in a database. A character set is a collection of characters with unique representations for each character, such as letters, numbers, and symbols, that define how data is …

In this blog post, we’ll discuss how to set a replication from MySQL 8.0 to MySQL 5.7. There are some situations that having this configuration might help. For example, in the case of a MySQL upgrade, it can be useful to have a master that is using a newer version of MySQL to an older version slave as a rollback plan. Another example is in the case of upgrading a master x master replication topology.

Officially, replication is only supported between consecutive major MySQL versions, and only from a lower version master to a higher version slave. Here is an example of a supported scenario:

5.7 master –> 8.0 slave

while the opposite is not supported:

8.0 master –> 5.7 slave

In this blog post, I’ll walk through how to overcome the …

Please join Percona’s Principal Technical Services Engineer, Sveta Smirnova as she presents “Troubleshooting Issues with MySQL Character Sets ” on March 9, 2017, at 11:00 am PST / 2:00 pm EST (UTC-8).

Register Now

Many MySQL novices find MySQL character sets support puzzling. But after you understand how it is designed, you will find it much more powerful than many other competing database solutions.

MySQL allows to specify a character set for every object, and change it online. For years this has helped to create fast applications that can work …