The database schema has changed between 8.x.x to 9.x.x.
Start with a clean database if you migrate from x.x.x to 9.x.x
The database schema has changed between 9.x.x to 10.x.x IF YOU ARE USING CLUSTERS.
Start with a clean database IF YOU ARE USING CLUSTERS migrate from x.x.x to 10.x.x or use migrations.js
from9to10
function.