I default to choosing either SQLite or PostgreSQL until there's sufficient reason to think about using something else. I think it's pretty rare to build an appl

I default to choosing either SQLite or PostgreSQL until there's sufficient reason to think about using something else. I think it's pretty rare to build an application where you know you will have scalability issues with a relational model, but I can tell you with confidence that if you ever do need to make changes to how your data is stored, you will be happy if the source is a datastore that has enforced integrity guarantees. It's much easier to migrate data from one system to another when you don't first have to check that it's all valid in the first place.