A database is so much more than just a schema and validator, but this is being advertised as a database replacement.
And, I want to stress, that this doesn't mean I don't think it isn't useful. I bet there are lots of times where you want to enforce some sort of structure on a bunch of folders with files in them. That's not a database though.
I have not used TreeBase for anything other than collaborative knowledge bases. Haven't even thought much beyond that. Thanks for letting me know that wasn't clear.
This is false. It is both.
A database is merely an application that provides an interface to structured data on disk.
I know a thing or two about databases, having contributed to a few of the larger open source ones.
There's a lot more to TreeBase than is on the website right now. As the website says "We have been using TreeBase for over 2 years in systems with millions of rows and dozens of collaborators." For all you know, you may have actually used a website that is powered by TreeBase (well, a TreeBase application written in a different host language, but the file system semantics are the same).
Can you point to a single place where I posted about TreeBase or TreeNotation that wasn't relevant to the context? I don't think you'll find a single example.