PopSQL co-founder here, if you choose to share your database host, port, and name with your team, then we'll store that on our servers, but never your database username and password. If you choose to get a link to share your results, the results are uploaded from your computer directly to S3. Hope that helps!
This is a key question! Also want to know as I’m considering signup and data security is a factor.
It seems to store the database URL on the server (popsql) but the username and password are stored in the Mac Keychain, any "team members" must enter the database username and password against when attempting to use the connection.