How to update Nextcloud Docker

I have a container installed with Nextcloud 19.4 and the tag 19.0.4. Now I want to install the latest version and upgrade to the latest version, wich is 20.0.

How can I do it?

Install a new container with the latest tag?
Remapp the config folder

and then it should work like in the old version, right?

I know the next question belong not here in this forum, but maybe you could answere it anyway.
I need to relink the databse from the old nextcloud 19 to the news nc20. Can I just login with the old user and pw and the new nextcloud will adopt the tables of the database?

Thanks for the help