DocDB and MySQL >= 4.1

MySQL added a reserved word Separator and DocDB versions < 8.2.1 and >= 8.0.0 use this word. If you upgraded to DocDB version 8 before version 8.2.1 your database is probably not compatible with recent versions of MySQL. This is easy to fix, just issue connect to MySQL for your DocDB database and issue the commands
"alter table Moderator drop key Separator",
"alter table Moderator add key SepKey (SessionSeparatorID)",
"alter table EventTopic drop key Separator",
"alter table EventTopic add key SepKey (SessionSeparatorID)",

before upgrading MySQL.