Re: Error upgrading from 5.7.28 to 8.0.17

[Peter Brawley]

Looks like the problems discussed at https://forums.mysql.com/read.php?11,673634,673734, and elsewhere ... apparently the problem's due to failure to run mysql_upgrade on 5.7 before upgrading to 8.0, so if there's a 5.7 backup, the recommendation has been to lose 8.0, get 5.7 working with restored data, run mysql_upgrade, also see ...

https://dev.mysql.com/doc/mysql-shell/8.0/en/mysql-shell-utilities-upgrade.html

https://mysqlserverteam.com/mysql-shell-8-0-4-introducing-upgrade-checker-utility/

https://mysqlserverteam.com/inplace-upgrade-from-mysql-5-7-to-mysql-8-0/

https://mysqlserverteam.com/upgrading-to-mysql-8-0-here-is-what-you-need-to-know/

https://www.slideshare.net/freshdaz/mysql-day-paris-2018-upgrade-from-mysql-57-to-mysql-80

... and only then upgrade to 8.0.