Going back to last version of NC with backup of DB and the Nextcloud-folder


i went from the latest 27 to the latest 28 - i have backup of the 27 DB and the last 27 nextcloud folder - but not from the data folder.

Is there a procedure to go back?
Only using the old db together with the nextcloud folder is not really running… have i missed something? Do i have to do something with the data folder?



I know this page - question was is there a way without the data directory? Because there is no change on the real data… only two folders were really updated - the whole huge amount of data is the same…