Comment 2 for bug 1787727

Hi,
your logs suggest that you tried to switch between mysql/mariadb which are incompatible.
I'm not sure what else to recommend than to follow exactly what was suggested by the messages you copied and posted here.

You have to decide to either retain the old DB data (and install the matching server) OR to throw everything away and start fresh with whatever sql server you want.

To carry over you could install the sevrer you had, make a backup, then remove everything (data and server) install the other server and then restore from backup.

But all that is already in the text you quoted.