Database vs privacy

I was just using logseq for two days and it looks very interesting. It seems to solve so many problems… :slight_smile:
Still, I have a question touching privacy. Seeing some responses on discord and articles like this one, it seems it is possible to change the database that is used during logseq usage. I expect this is something different than the storage holding actual markdown files (local folder, github…).
How can I know/see what actual database is used to process my “private” thinking process? I assume it can be local browser-based one, but can it be also other local/cloud ones?
Best regards,