There are certainly differences between the pricing models for these enterprise databases. They are actively developed and have different feature sets, although

There are certainly differences between the pricing models for these enterprise databases. They are actively developed and have different feature sets, although you might need to look carefully to distinguish between them. There is active competition here (https://redmondmag.com/articles/2016/03/10/sql-server-2016-oracle.aspx https://redmondmag.com/articles/2016/03/10/sql-server-2016-o...). Postgresql is good but lacks some of the polish and features of the paid for databases. Availability and cost of skilled staff and compatibility with existing deployments might also be important. So not critical differences perhaps but squint hard enough and you'll see there are differences nonetheless.