Thanks for this. Great help for those of us who like to play but do not have a lot of exp with the deeper end of servers. I have not used all the guides(yet) but got my way through some of them. I do have a couple questions. You said you have a larger Nextcloud server on your postgres DB. Did you have to substantially increase the max_connections? Once I installed max_connections was set to 100 (default). My nextcloud docker when running with the maps app installed would start throwing out Doctrine\DBAL\Exception: Failed to connect to the database: An exception occurred in the driver: SQLSTATE[08006] [7] FATAL: remaining connection slots are reserved for non-replication superuser connections and Doctrine\DBAL\Exception: Failed to connect to the database: An exception occurred in the driver: SQLSTATE[08006] [7] FATAL: sorry, too many clients already. One of the searches I found stated that it could be client connections are not closing on the backend side and as a temp measure to increase max_connections. I increased to 200 then hit the NC server with a maps refresh and it quickly rose from 8-9 connections to 127-129 connections to the DB (watched through the query tool in pgAdmin) but then dropped back down to 8-9 connections not long after. I ask this as I did not find much in my google search with this error related to Nextcloud so I assume I either misconfigured something or, everyone else is just smart enough to increase max_connections to begin with.
Also, in the Nextcloud guide you referenced a "go" file for DB tuning. Where would one find this, or if I missed a guide that has this mentioned in more detail can you point me in its direction? Would like to read up on that some more.
Attached image with the database errors. I know there are other errors as well (I think they are directly related to the maps app) that I will look into later but I am focused on the DB errors as those one bring Nextcloud to a halt.