After performing a restart of our Confluence server, I get database collation is not supported

[Cesar Ramos]

Hi!

After performing a restart of our Confluence server, I got the following message:

Database: The database collation 'utf8mb3_bin' is not supported by Confluence. You need to use 'utf8_bin, utf8mb4_bin'.

I was not performing any updates or upgrades. 

Confluence Build Number: 8402 (7.4)

MySQL version: 8.0.30

character_set_database utf8mb3
collation_database utf8mb3_bin
character_set_server utf8mb3

[Ian Jackson]

We've found that simply declaring utf8 and utf8-bin will not suffice. You now have to explicitly use "utf8mb4" and "utf8mb4_bin."

UTF8 and UTF8-bin is an alias to "utf8mb3" and "utf8mb3-bin" it alone will not suffice.

We don't know why the installation was successful using utf8, utf8-bin but now that Atlassian recommends this, you need to alter your DB, tables and columns to use these formats.

This is outlined here:

https://confluence.atlassian.com/kb/how-to-fix-the-collation-and-character-set-of-a-mysql-database-manually-744326173.html