Upgrading: OC 8.2.1 to NC 9.0.5

Would you happen to have any suggestions on how to do this without losing any data (database)? I have tried a couple of times to do this, the upgrade process keeps complaining that certain tables already exist (i.e. oc_trusted…). Sorry I forgot the table name. Additionally the process also mentioned some sort of federation error, I’m not using federation.

There is a similar topic: Several issues known from OC
and a related issue on github: https://github.com/nextcloud/server/issues/120

@tflidd have a look at this issue: https://github.com/nextcloud/server/issues/297

As one of the forum issues indicated “…just ignore it as suggested on github.”. Even if I keep dropping the tables in the database, Nextcloud keeps going through the upgrade process. So the “errors” cannot be ignored. These errors occur in ownCloud and Nextcloud when upgrading from ownCloud 8.2.1 to Nextcloud 9 for me.

So I am seeking some sort of resolution. I am sure I am not the only user that has “data collections” in ownCloud 8.2.1 that one would not want to lose. These errors probably are keeping a lot of people from upgrading to the newest versions of ownCloud or even migrating over to Nextcloud.

Does anyone have any answers other than to keep dropping tables?

Normally it is recommended to update to the latest version of the 8.2.x branch (8.2.7) first. If there are still issues, that has to be solved by the developers on github.