Databases using Azure Database for MySQL on version 5.7.27-log allows using . (dot) in database names. Setup of Strapi using MySQL does not allowed this. This causes one to create a temporary database that does not have a dot in the name, set permissions, do the setup, change database name and then update database.json.

Edit: Also true for Postgres.

See: https://github.com/strapi/strapi/issues/5267