Last Month, I went to the Brisbane.net user group. The topic is PostgreSQL.PostgreSQL? How can it be related to .Net? You may think that that is more related to Linux. That is not. Azure got Postsqesql implementation, which is customized for Azure. Thus, that is performance quite good.
Moreover, that is more than half the price of the MS SQL server option. Lastly, EF core is fully supported by Postgresql. They are very suitable for a small-scale project. I will explore it for my membership management system.