For the Software as a Service version, we were using PostgreSQL on Ubuntu and paid some amount. It was not a very large amount for PostgreSQL on Ubuntu. We were on the lowest tier, so it was around $5 or something.
PostgreSQL on Ubuntu is the #31 ranked solution in top Operating Systems for Business. PeerSpot users give PostgreSQL on Ubuntu an average rating of 8.6 out of 10.
For the Software as a Service version, we were using PostgreSQL on Ubuntu and paid some amount. It was not a very large amount for PostgreSQL on Ubuntu. We were on the lowest tier, so it was around $5 or something.
PostgreSQL on Ubuntu is free of cost. We are not purchasing anything additional.