Secure access to an on-premise database

Hello

We are trying to deploy a streamlit application in the cloud.
The application connects to a PostgreSQL which is hosted within our sub-network, and without public/internet access.
What would be a way to access the on-prem database?
We are thinking of two possibilities:

  • Some kind of gateway
  • Streamlit cloud could VPN to our sub-network, and connect to the DB

Any thoughts please?