As said, I’m using a “fully installed” nextcloud, but I think your source of info is Nextcloud’s docker container readme., section Using the Nextcloud command-line interface.
Summarized:
- Nextcloud container (not mysql etc. nested containers)
- user
www-dataas above, = Apache owner
On my machine occ is not located in $PATH, so I have to start fully qualified, it’s located directly in Nextcloud’s main folder.