Some users have problems with
brew upgrade and using Homebrew MySQL from 5.* to 8.
When enter to mysql -uroot, and enter
SHOW DATABASES; returns the error: Mysql Error:The user specified as a definer (‘mysql.infoschema’@’localhost’) does not exist’ when trying to dump tablespaces
To solve this, follow:
mysql -u root -p
mysql> SET GLOBAL innodb_fast_shutdown = 1;
mysql_upgrade -u root -p
Done! It works!